Archive for the ‘computer science’ Category

This is going to strike people as a rant, but it’s not. It’s a recommendation to the fields of software engineering, and by extension, computer science, at large, on how to elevate the discussion in software engineering. This post was inspired by a question I was asked to answer on Quora about whether object-oriented programming or functional programming offers better opportunities for modularizing software design into simpler units.

So, I’ll start off by saying that what software engineering typically calls “OOP” is not what I consider OOP. The discussion that this question was about is likely comparing abstract data types, in concept, with functional programming (FP). What they’re also probably talking about is how well each programming model handles data structures, how the different models implement modular functionality, and which is preferable for dealing with said data structures.

Debating stuff like this is so off from what the discussion could be about. It is a fact that if an OOP model is what is desired, one can create a better one in FP than what these so-called “OOP” proponents are likely talking about. It would take some work, but it could be done. It wouldn’t surprise me if there already are libraries for FP languages that do this.

The point is what’s actually hampering the discussion about what programming model is better is the ideas that are being discussed, and more broadly, the goals. A modern, developed engineering discipline would understand this. Yes, both programming models are capable of decomposing tasks, but the whole discussion about which does it “better” is off the mark. It has a weak goal in mind.

I remember recently answering a question on Quora regarding a dispute between two people over which of two singers, who had passed away in recent years, was “better.” I said that you can’t begin to discuss which one was better on a reasonable basis until you look at what genres they were in. In this case, I said each singer used a different style. They weren’t trying to communicate the same things. They weren’t using the same techniques. They were in different genres, so there’s little point in comparing them, unless you’re talking about what style of music you like better. By analogy, each programming model has strengths and weaknesses relative to what you’re trying to accomplish, but in order to use them to best effect, you have to consider whether each is even a good fit architecturally for the system you’re trying to build. There may be different FP languages that are a better fit than others, or maybe none of them fit well. Likewise, for the procedural languages that these proponents are probably calling “OOP.” Calling one “better” than another is missing the point. It depends on what you’re trying to do.

Comparisons about programming models in software engineering tend to wind down to familiarity, at some point; which languages can function as a platform that a large pool of developers know how to use, because no one wants to be left holding the bag if developers decide to up and leave. I think this argument misses a larger problem: How do you replace the domain knowledge those developers had? The most valuable part of a developer’s knowledge base is their understanding of the intent of the software design; for example, how the target business for the system operates, and how that intersects with technical decisions that were made in the software they worked on. Usually, that knowledge is all in their heads. It’s hardly documented. It doesn’t matter that you can replace those developers with people with the same programming skills, because sure, they can read the code, but they don’t understand why it was designed the way it was, and without that, it’s going to be difficult for them to do much that’s meaningful with it. That knowledge is either with other people who are still working at the same business, and/or the ones who left, and either way, the new people are going to have to be brought up to speed to be productive, which likely means the people who are still there are going to have to take time away from their critical duties to train the new people. Productivity suffers even if the new people are experts in the required programming skills.

The problem with this approach, from a modern engineering perspective, goes back to the saying that if all someone knows how to use is a hammer, every problem looks like a nail to them. The problem is with the discipline itself; that this mentality dominates the thinking in it. And I must say, computer science has not been helping with this, either. Rather than exploring how to make the process of building a better-fit programming model easier, they’ve been teaching a strict set of programming models for the purpose of employing students in industry. I could go on about other nagging problems that are quite evident in the industry that they are ignoring.

I could be oversimplifying this, but my understanding is modern engineering has much more of a form-follows-function orientation, and it focuses on technological properties. It does not take a pre-engineered product as a given. It looks at its parts. It takes all of the requirements of a project into consideration, and then applies analysis technique and this knowledge of technological properties to finding a solution. It focuses a lot of attention on architecture, trying to make efficient use of materials and labor, to control costs. This focus tends to make the scheduling and budgeting for the project more predictable, since they are basing estimates on known constraints. They also operate on a principle that simpler models (but not too simple) fail less often, and are easier to maintain than overcomplicated ones. They use analysis tools that help them model the constraints of the design, again, using technological properties as the basis, taking cognitive load off of the engineers.

Another thing is they don’t think about “what’s easier” for the engineers. They think about “what’s easier” for the people who will be using what’s ultimately created, including engineers who will be maintaining it, at least within cost constraints, and reliability requirements. The engineers tasked with creating the end product are supposed to be doing the hard part of trying to find the architecture and materials that fit the requirements for the people who will be using it, and paying for it.

Clarifying this analogy, what I’m talking about when I say “architecture” is not, “What data structure/container should we use?” It’s more akin to the question, “Should we use OOP or FP,” but it’s more than that. It involves thinking about what relationships between information and semantics best suite the domain for which the system is being developed, so that software engineers can better express the design (hopefully as close to a “spec” as possible), and what computing engine design to use in processing that programming model, so it runs most efficiently. When I talk about “constraints of materials,” I’m analogizing that to hardware, and software runtimes, and what their speed and load capacity is, in terms of things like frequency of requests, and memory. In short, what I’m saying is that some language and VM/runtime design might be necessary for this analogy to hold.

What this could accomplish is ultimately documenting the process that’s needed—still in a formal language—and using that documentation to run the process. So, rather than requiring software engineers to understand the business process, they can instead focus on the description and semantics of the engine that allows the description of the process to be run.

What’s needed is thinking like, “What kind of system model do we need,” and an industry that supports that kind of thinking. It needs to be much more technically competent to do this. I know this is sounding like wishful thinking, since people in the field are always trying to address problems that are right in front of them, and there’s no time to think about this. Secondly, I’m sure it sounds like I’m saying that software engineers should be engaged in something that’s impossibly hard, since I’m sure many are thinking that bugs are bad enough in existing software systems, and now I’m talking about getting software engineers involved in developing the very languages that will be used to describe the processes. That sounds like I’m asking for more trouble.

I’m talking about taking software engineers out of the task of describing customer processes, and putting them to work on the syntactic and semantic engines that enable people familiar with the processes to describe them. Perhaps I’m wrong, but I think this reorientation would make hiring programming staff based on technical skills easier, in principle, since not as much business knowledge would be necessary to make them productive.

Thirdly, “What about development communities?” Useful technology cannot just stand on its own. It needs an industry, a market around it. I agree, but I think, as I already said, it needs a more technically competent industry around it, one that can think in terms of the engineering processes I’ve described.

It seems to me one reason the industry doesn’t focus on this is we’ve gotten so used to the idea that our languages and computing systems need to be complex, that they need to be like Swiss Army knives that can handle every conceivable need, because we seem to need those features in the systems that have already been implemented. They reality is the reason they’re complex is a) they have been built using semantic systems that are not well suited to the problem they’re trying to solve, and b) they’re really designed to be “catch all” systems that anticipate a wide variety of customer needs. So, the problem you’re trying to solve is but a subset of that. We’ve been coping with the “Swiss Army knife” designs of others for decades. What’s actually needed is a different knowledge set that eschews from the features we don’t need for the projects we want to complete, that focuses on just the elements that are needed, with a practice that focuses on design, and its improvement.

Very few software engineers and computer scientists have had the experience of using a language that was tailored to the task they were working on. We’ve come to think that we need feature-rich languages and/or feature-rich libraries to finish projects. I say no. That is a habit, thinking that programming languages are communication protocols not just with computers, but with software engineers. What would be better is a semantic design scheme for semantic engines, having languages on top of them, in which the project can be spec’d out, and executed.

As things stand, what I’m talking about is impractical. It’s likely there are not enough software engineers around with the skills necessary to do what I’m describing to handle the demand for computational services. However, what’s been going on for ages in software engineering has mostly been a record of failure, with relatively few successes (the vast majority of software projects fail). Discussions, like the one described in the question that inspired this post, are not helping the problem. What’s needed is a different kind of discussion, I suggest using the topic scheme I’ve outlined here.

I’m saying that software engineering (SE) needs to take a look at what modern engineering disciplines do, and do their best to model that. CS needs to wonder what scientific discipline it can most emulate, which is what’s going to be needed if SE is going to improve. Both disciplines are stagnating, and are being surpassed by information technology management as a viable solution scheme for solving computational problems. However, that leads into a different problem, which I talked about 9 years ago in IT: You’re doing it completely wrong.

Related posts:

Alan Kay: Rethinking CS education

The future is not now

— Mark Miller, https://tekkie.wordpress.com

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It’s been 5 years since I’ve written something on SICP–almost to the day! I recently provided some assistance to a reader of my blog on this exercise. In the process, I of course had to understand something about it. Like with Exercise 1.19, I didn’t think this one was written that clearly. It seemed like the authors assumed that the students were familiar with the Miller-Rabin test, or at least modular mathematics.

The exercise text made it sound like one could implement Miller-Rabin as a modification to Fermat’s Little Theorem (FLT). From providing my assistance, I found out that one could do it as a modification to FLT, though the implementation looked a bit convoluted. When I tried solving it myself, I felt more comfortable just ignoring the prior solutions for FLT in SICP, and completely rewriting the expmod routine. Along with that, I wrote some intermediate functions, which produced results that were ultimately passed to expmod. My own solution was iterative.

I found these two Wikipedia articles, one on modular arithmetic, the other on Miller-Rabin, to be more helpful than the SICP exercise text in understanding how to implement it. Every article I found on Miller-Rabin, doing a Google search, discussed the algorithm for doing the test. It was still a bit of a challenge to translate the algorithm to Scheme code, since they assumed an imperative style, and there is a special case in the logic.

It seemed like when it came right down to it, the main challenge was understanding how to calculate factors of n – 1 (n being the candidate tested for primality), and how to handle the special case, while still remaining within the confines of what the exercise required (to do the exponentiation, use the modulus function (remainder), and test for non-trivial roots inside of expmod). Once that was worked out, the testing for non-trivial roots turned out to be pretty simple.

If you’re looking for a list of primes to test against your solution, here are the first 1,000 known primes.

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I thought I’d share the video below, since it has some valuable insights on what computer science should be, and what education should be, generally. It’s all integrated together in this presentation, and indeed, one of the projects of education should be integrating computer science into it, but not with the explicit purpose to create more programmers for future jobs, though it could always be used for that by the students. Alan Kay presents a different definition of CS than is pursued in universities today. He refers to how Alan Perlis defined it (Perlis was the one to come up with the term “computer science”), which I’ll get to below.

This thinking about CS and education provides, among other things, a pathway toward reimagining how knowledge, literature, and art can be presented, organized, dissected, annotated, and shared in a way that’s more meaningful than can be achieved with old media. (For more on that, see my post “Getting beyond paper and linear media.”) As with what the late Carl Sagan often advocated, Kay’s presentation here advocates for a general model for the education of citizens, not just professional careerists.

Another reason I thought of sharing this is several years ago I remember hearing that Kay was working on rethinking computer science curriculum. What he presents is more about suggestion, “Start thinking about it this way.” (He takes a dim view of the concept of curriculum, as it suggests setting students on a rigid path of study with the intent to create minds with a cookie cutter, though he is in favor of classical liberal arts education, with the prescriptions that entails.)

As he says in the presentation, there’s a lot to develop in the practice of education in order to bring this into fruition.

This is from 2015:

I wrote notes below for some of the segments he talks about, just because I think his presentation bears some interpretation for many readers. He uses metaphors a lot.

The bicycle

This is an analogy for how an apparatus, or a subject, is typically modified for education. We take the optimized, or the adult version of something, and add compensators, which make it so that beginners can use it without falling all over themselves. It’s seen as easier to present it this way, and as a skill-building experience, where in order to learn how to do something, you need to use “the real thing.” Beginners can put on a good show of using this sort of apparatus, or modified subject, but the problem is that it doesn’t teach a beginner how to become good at really using the real thing at its full potential. The compensators become a crutch. He said a better idea is to use an apparatus, or a component of the subject, that allows a beginner to get a feel for how to use the thing in a way that gets across significant aspects of its potential, but without the optimizations, or the way adults use it, which make it too complicated for a beginner to use under their own power. In this case, a lowbike is better. This beginner apparatus, or component, is more like the first version of the thing you’re trying to teach. Bicycles were originally more like scooters, without pedals, or a chain, where you’d sit in the seat, push it along with your legs, kind of “running while sitting,” glide, and turn by shifting your weight, and turning into the turn. Once a beginner gets a feel for that, they can deal with the optimized version, or a scaled down adult version, with pedals and a chain to drive the bike, because all that adds is the ability to get more power out of it. It doesn’t change any of the fundamentals of how you use it.

This gets to an issue of pedagogy, that learners need to learn something in components, rather than dealing with the whole thing at once. Once they learn one capacity, they can move on to the next challenge in learning the “whole thing.”

Radiation vs. nouns

He put forward a proposition for his talk, which is that he’s mixing a bunch of ideas together, because they overlap. This is a good metaphor, because most of his talk is about what we are as human beings, and how society should situate and view education. Only a little of it is actually on computer science, but all of it is germane to talking about computer science education.

He also gives a little advice to education reformers. He pointed out what’s wrong with education as it is right now, but rather than cursing it, he said one should make a deliberate effort to “build a tribe” or coalition with those who are causing the problem, or are in the midst of the problem, and suggest ways to bring them into a dignified position, perhaps by sharing in their honors, or, as his example illustrated, their shame. I draw some of this from Plato’s Cave metaphor.

Cooperation and competition in society

I once heard Kay talk about this many years ago. He said that, culturally, modern corporations are like the ancient hunter-gatherers. They exploit the resources of an area for a while, and once it’s exhausted, they move on, and that as a culture, they have yet to learn about democracy, which requires more of a “settlement” mentality toward what they’re doing. Here, he used an agricultural metaphor to talk about a cooperative society that creates the wealth that is then used by competitive forces within it. What he means by this is that the true wealth is the knowledge that’s ultimately used to develop new products and services. It’s not all developed inside the marketplace. He doesn’t talk about this, but I will. Even though a significant part of the wealth (as he said, you can think of it as “potential energy”) is generated inside research labs, what research labs tend to lack is knowledge of what the members of society can actually understand of this developed knowledge. That’s where the competitive forces in society come in, because they understand this a lot better. They can negotiate between how much of the new knowledge to put into a product, and how much it will cost, to reach as many people as possible. This is what happened in the computer industry of the past.

I think I understand what he’s getting at with the agricultural metaphor, because farmers don’t just want to reap a crop for one season. Their livelihood depends on maintaining fertility on their land. That requires not just exploiting what’s there season after season, or else you get the dust bowl. If instead, practices are modified to allow the existing land to become fertile again, or, in the case of hunter-gathering, aggressively managing the environment to create favorable grazing to attract game, then you can create a cycle of exploitation and care such that a group can stay in one area for a long time, without denying themselves any of the benefits of how they live. I think what he suggests is that if corporations would modify their behavior to a more settled, agricultural model, to use some of their profits to contribute to educating the society in which they exist, and to funding scientific research on a private basis, that would “regenerate the soil” for economic growth, which can then fuel more research, creating a cycle of renewal. No doubt the idea he’s presenting includes the businesses who would participate in doing this. They should be allowed to profit (“reap”) from what they “sow,” but the point is they’re not the only ones who can profit. Other players in the marketplace can also exploit the knowledge that’s generated, and profit as well. That’s what’s been done in the past with private research labs.

He attributes the lack of this to culture, of not realizing that the economic model that’s being used is not sustainable. Eventually, you use up the “soil,” and it becomes “infertile,” and “blows away,” and, in the case of hunter-gathering, the “good hunting grounds” are used up.

He makes a crucial point, though, that education is not just about jobs and competitiveness. It’s also about inculcating what citizenship really means. I’m sure if he was asked to drill down on this more, he would suggest a classical education for this, along with a modified math and science curriculum that would give students a sense of what those subjects really are like.

The sense I get is he’s advocating almost more of an Andrew Carnegie model of corporate stewardship, who, after he made his money, directed his philanthropy to building schools and libraries. Kay would just add science labs to that mix. (He mentions this later in his talk.)

I feel it necessary to note that not all for-profit entities would be able to participate in funding these cooperative activities, because their profit margins are so slim. I don’t think that’s what he’s expecting out of this.

What we are, to the best of our knowledge

He gives three views into human mental capacity: the way we perceive (theatrical), how much we can perceive at any moment in time (1 ± 2), and how educators should perceive ourselves psychologically and mentally (more primate and mammalian). This relates to neuroscience, and to some extent, evolutionary psychology.

The raison d’être of computer science

The primary purpose of computer science should be developing a science of systems in process, and that means all processes: mechanical processes, technological processes, social processes, biological processes, mental processes, etc. This relates to my earlier post, “Beginning the journey of becoming a computer scientist.” It’s partly about developing a new kind of mathematics for modeling processes. Alan Turing did it, with his Turing Machine concept, though he was trying to model the process of generating mathematical statements, and doing mathematical tests on them.

Shipping the design

Kay talks about how programmers today don’t have access to anything like what designers in other fields have, where they’re able to model their design, simulate it, and then have a machine fabricate a prototype that you can actually show and use.

I had an epiphany about this about 8 or 9 years ago. I was at a friend’s party, and there were a few mechanical engineers among the guests. I overheard a couple of them talking about the computer-aided design (CAD) software they were using. One talked about a “terrible” piece of CAD software he used at work. He said he had a much better CAD system at home, but it was incompatible with the data files that were used at work. As much as he would’ve loved to use it, he couldn’t. He said the system he used at work required him to group pieces of a design together as he was building the model, and once he did that, those pieces became inflexible. He couldn’t just redesign one piece of it, or separate one out individually from the model. He couldn’t move the pieces around on the model, and have them fit. Once they were grouped, that was it. It became this static thing. He said in order to redesign one piece of it, he had to take the entire model apart, piece by piece, redesign the part, and then redesign all the other pieces in the group to make the new part fit. He said he hated it, and as he talked about it, he acted like he was so disgusted with it, he wanted to throw it in the trash, like it was a piece of garbage. He said on his CAD system at home, it was wonderful, because he could separate a part from a model any time he wanted, and the system would adjust the model automatically to “make sense” out of the part being missing. He could redesign the part, and move it to a different part of the model, “attach it” somewhere, and the system would automatically adjust the model so that the new part would fit. The way he described it gave it a sense of fluidity. Whereas the system he used at work sounded rigid. It reminded me of the programming languages I had been using, where once relationships between entities were set up, it was really difficult to take pieces of it “out” and redesign them, because everything that depended on that piece would break once I redesigned it. I had to go around and redesign all the other entities that related to it to adjust to the redesign of the one piece.

I can’t remember how this worked, but another thing the engineer talked about was the system at work had some sort of “binding” mechanism that seemed to associate parts by “type,” and that this was also rigid, which reminded me a lot of the strong typing system in the languages I had been using. He said the system he had at home didn’t have this, and to him, it made more sense. Again, his description lent a sense of fluidity to the experience of using it. I thought, “My goodness! Why don’t programmers think like this? Why don’t they insist that the experience be like this guy’s CAD system at home?” For the first time in my career, I had a profound sense of just what Alan Kay talked about, here, that the computing field is retrograde. It has not advanced anywhere close to the kind of engineering that exists in other fields, where they would insist on this sort of experience. We accept so much less, whereas modern engineers have a hard time standing for it, because they know they have better options.

Don’t be fooled by large efforts below threshold

Before I begin this part, I want to share a crucial point that Kay makes, because it’s one of the big ones:

Think about what thinking is. Thinking is not being logical. Thinking is choosing the environment that you’re going to think in before you start rationalizing.

Kay had something very interesting, and startling, to say about the Apollo space program, using that as a metaphor for large reform initiatives in education generally. I recently happened upon a video of testimony he gave to a House committee on educational computing back in 1982, chaired by then-congressman Al Gore, and Kay talked about this same example back then. He said that the way the Apollo rockets were designed was a “hack.” They were not the best design for space travel, but it was the most expedient for the mission of getting to the Moon by the end of the 1960s. Here, in this presentation, he talks about how each complete rocket was the height of a 45-story building (1-1/2 football fields in length), most of it high explosives, with only a tiny capsule at the top that could fit 3 astronauts. This is not a model that could scale to what was needed for space travel.

It became this huge worldwide cultural event when NASA launched it, and landed men on the Moon, but Kay said it was really not a great accomplishment. I remember Rep. Gore said in jest, “The walls in this room are shaking!” The camera panned around a bit, showing pictures on the wall from NASA. How could he say such a thing?! This was the biggest cultural event of the century, perhaps in all of human history. He explained the same thing here: that the Apollo program didn’t advance space travel beyond the mission to the Moon. It was not technology that would get us beyond that, though, in hindsight we can say technology like it enabled launching probes throughout the Solar System.

Now, what he means by “space travel,” I’m not sure. Is it manned missions to the outer planets, or to other star systems? Kay is someone who has always thought big. So, it’s possible he was thinking of interstellar travel. What he was talking about was the problem of propulsion, getting something powerful enough to make significant discoveries in space exploration possible. He said chemical propellant just doesn’t do it. It’s good enough for launching orbital vehicles around our planet, and launching probes, but that’s really it. The rest is just wasting time below threshold.

Another thing he explained is that large initiatives which don’t cross a meaningful threshold can be harmful to efforts to advancing any endeavor, because large initiatives come with extended expectations that the investment will continue to be used, and they must be satisfied, or else there will be no cooperation in doing the initial effort. The participants will want their return on investment. He said that’s what happened with NASA. The ROI had to play out, but that ruined the program, because as that happened, people could see we weren’t advancing the state of the art that much in space travel, and the science that was being produced out of it was usually nothing to write home about. Eventually, we got what we now see: People are tired of it, and have no enthusiasm for it, because it set expectations so low.

What he was trying to do in his House committee testimony, and what he’s trying to do here, is provide some perspective that science offers, vs. our common sense notion of how “great” something is. You cannot get qualitative improvement in an endeavor without this perspective, because otherwise you have no idea what you’re dealing with, or what progress you’re building on, if any. Looking at it from a cultural perspective is not sufficient. Yes, the Moon landing was a cultural milestone, but not a scientific or engineering milestone, and that matters.

Modern science and engineering have a sense of thresholds, that there can come a point where some qualitative leap is made, a new perspective on what you’re doing is realized that is significantly better than what existed prior. He explains that once a threshold has been crossed, you can make small improvements which continue to build on that significant leap, and those improvements will stick. The effort won’t just crash back down into mediocrity, because you know something about what you have, and you value it. It’s a paradigm shift. It is so significant, you have little reason to go back to what you were doing before. From there, you can start to learn the limits of that new perspective, and at some point, make more qualitative leaps, crossing more thresholds.

“Problem-finding”/finding the goal vs. problem-solving

Problem solving begins with a current context, “We’re having a problem with X. How do we solve it?” Problem finding asks do we even have a good idea of what the problem is? Maybe the reason for the problems we’ve been seeing has to do with the fact that we haven’t solved a different problem we don’t know about yet. “Let’s spend time trying to find that.”

Another way of expressing this is a concept I’ve heard about from economists, called “opportunity cost,” which, in one context, gets across the idea that by implementing a regulation, it’s possible that better outcomes will be produced in certain categories of economic interactions, but it will also prevent certain opportunities from arising which may also be positive. The rub is these opportunities will not be known ahead of time, and will not be realized, because the regulation creates a barrier to entry that entrepreneurs and investors will find too high of a barrier to overcome. This concept is difficult to communicate to many laymen, because it sounds speculative. What this concept encourages people cognizant of it to do is to “consider the unseen,” to consider the possibilities that lie outside of what’s currently known. One can view “problem finding” in a similar way, not as a way of considering the unseen, but exploring it, and finding new knowledge that was previously unknown, and therefore unseen, and then reconsidering one’s notion of what the problem really is. It’s a way of expanding your knowledge base in a domain, with the key practice being that you’re not just exploring what’s already known. You’re exploring the unknown.

The story he tells about MacCready illustrates working with a good modeling system. He needed to be able to fail with his ideas a lot, before he found something that worked. So he needed a simple enough modeling system that he could fail in, where when he crashed with a particular model, it didn’t take a lot to analyze why it didn’t work, and it didn’t take a lot to put it back together differently, so he could try again.

He made another point about Xerox PARC, that it took years to find the goal, and it involved finding many other goals, and solving them in the interim. I’ve written about this history at “A history lesson on government R&D” Part 2 and Part 3. There, you can see the continuum he talks about, where ARPA/IPTO work led into Xerox PARC.

This video with Vishal Sikka and Alan Kay gives a brief illustration of this process, and what was produced out of it.

Erosion gullies

There are a couple metaphors he uses to talk about the lack of flexibility that develops in our minds the more we focus our efforts on coping, problem solving, and optimizing how we live and work in our current circumstances. One is erosion gullies. The other is the “monkey trap.”

Erosion gullies channel water along a particular path. They develop naturally as water erodes the land it flows across. These “gullies” seem to fit with what works for us, and/or what we’re used to. They develop into habits about how we see the world–beliefs, ideas which we just accept, and don’t question. They allow some variation in the path that’s followed, but they provide boundaries that don’t allow the water to go outside the gully (leaving aside the exception of floods, for the sake of argument). He uses this to talk about how “channels” develop in our minds that direct our thinking. The more we focus our thoughts in that direction, the “deeper” the gully gets. Keep at it too long, and the “gully” won’t allow us to see anything different than what we’re used to. He says that it may become inconceivable to think that you could climb out of it. Most everything inside the “gully” will be considered “right” thinking (no reason why), and anything outside of it will be considered “wrong” (no reason why), and even threatening. This is why he mentions that wars are fought over this. “We’re all in different erosion gullies.” They don’t meet anywhere, and my “right” is your “wrong,” and vice-versa. The differences are irreconcilable, because the idea of seeing outside of them is inconceivable.

He makes two points with this. One is that we have erosion gullies re. stories that we tell ourselves, and beliefs that we hold onto. Another is that we have erosion gullies even in our sensory perceptions that dictate what we see and don’t see. We can see things that don’t even exist, and typically do. He uses eyewitness testimony to illustrate this.

I think what he’s saying with it is we need to watch out for these “gullies.” They develop naturally, but it would be good if we had the flexibility to be able to eventually get out of our “gully,” and form a new “channel,” which I take is a metaphor for seeing the world differently than what we’re used to. We need a means for doing that, and what he proposes is science, since it questions what we believe, and tests our ideas. We can get around our beliefs, and thereby get out of our “gullies” to change our perspective. It doesn’t mean we abandon “gullies,” but just become aware that other “channels” (perspectives) are possible, and we can switch between them, to see better, and achieve better outcomes.

Regarding the “monkey trap,” he uses it as a metaphor for us getting on a single track, grasping for what we want, not realizing that the very act of being that focused, to the exclusion of all other possibilities, is not getting us anywhere. It’s a trap, and we’d benefit by not being so dogged in pursuing goals if they’re not getting us anywhere.

“Fast” vs. “slow”

He gets into some neuroscience that relates to how we perceive, what he called “fast” and “slow” response. You can train your mind through practice in how to use “fast” and “slow” for different activities, and they’re integral to our perception of what we’re doing, and our reactions to it, so that we don’t careen into a catastrophe, or miss important ideas in trying to deal with problems. He said that cognitive approaches to education deal with the “slow” systems, but not the “fast” ones, and it’s not enough to help students in really understanding a subject. As other forms of training inherently deal with the “fast” systems, educators need to think about how the “fast” systems responds to their subjects, and incorporate that into how they are taught. He anticipates this will require radically redesigning the pedagogy that’s typically used.

He says that the “fast” systems deal with the “atoms” of ideas that the “slow” system also deals with. By “atoms,” I take it he means fundamental, basic ideas or concepts for a subject. (I think of this as the “building blocks of molecules.”)

The way I take this is that the “slow” systems he’s talking about are what we use to work out hard problems. They’re what we use to sit down and ponder a problem for a while. The “fast” systems are what we use to recognize or spot possible patterns/answers quickly, a kind of quick, first-blush analysis that can make solving the problem easier. To use an example, you might be using “fast” systems now to read this text. You can do it without thinking about it. The “slow” systems are involved in interpreting what I’m saying, generating ideas that occur to you as you read it.

This is just me, but “fast” sounds like what we’d call “intuition,” because some of the thinking has already been done before we use the “slow” systems to solve the rest. It’s a thought process that takes place, and has already worked some things out, before we consciously engage in a thought process.


This is the clearest expression I’ve heard Kay make about what science actually is, not what most people think it is. He’s talked about it before in other ways, but he just comes right out and says it in this presentation, and I hope people watching it really take it in, because I see too often that people take what they’ve been taught about what science is in school and keep reiterating it for the rest of their lives. This goes on not only with people who love following what scientists say, but also in our societal institutions that we happen to associate with science.

…[Francis] Bacon wrote a book called “The Novum Organum” in 1620, where he said, “Hey, look. Our brains are messed up. We have bad brains.” He called the ways of messing up “idols.” He said we get serious errors because of our genetics. We get serious errors because of the culture we’re in. We get serious errors because of the languages we use. They don’t represent what’s actually out there. We get serious errors from the way that academia hangs on to bad ideas, and teaches them over again. These are his four “idols.” Anyone ever read Bacon? He said we need something to get around our bad brains! A set of heuristics, is the term we’d use today.

What he called for was … science, because that’s what “Novum Organum,” the rest of the title, was: “A new way of dealing with knowledge.”

Science is not the knowledge, because knowledge is in this context. What science is is a negotiation between what’s out there and what we can represent.

This is the big idea. This is the idea they don’t teach in school. This is the idea we should be teaching. It’s one of the biggest ideas of all time.

It isn’t the knowledge. It’s the relationship, because what’s out there is only knowable by a phenomena that is being filtered in every possible way. We don’t even know if our brain is capable of representing the stuff.

So, to think about science as the truth is completely wrong! It’s not the right way to look at it. But if you think about it as a negotiation between the best you can do right now and stuff that’s out there, where you’re not completely sure, you’re in a very strong position.

Science has been the most important, powerful thought system humans have ever invented, because it gave up the idea of truth, and it substituted for it a thousand variations of false, some of which are incredibly powerful. This is the big idea.

So, if we’re going to think about computing, this is one way … of thinking about, “Wow! Computers!” They are representers. We can learn about representations. We can simulate ideas. We can get a very good–much better sense of dealing with thinking about these complexities.

“Getting there”

The last part demonstrates what I’ve seen with exploration. You start out thinking you’re going to go from Point A to Point B, but you take diversions, pathways that are interesting, but related to your initial search, because you find that it’s not a straight path from Point A to Point B. It’s not as straightforward as you thought. So, you try other ways of getting there. It is a kind of problem solving, but it’s really what Kay called “problem finding,” or finding the goal. In the process, the goal is to find a better way to get to the goal, and along the way, you find problems that are worth solving, that you didn’t anticipate at all when you first got going. In that process, you’ll find things you didn’t expect to learn, but which are really valuable to your knowledge base. In your pursuit of trying to find a better way to get to your destination, you might even get through a threshold, and find that your initial goal is no longer worth pursuing, but there are better goals to pursue in this new perception you’ve obtained.

Related post: Reviving programming as literacy

—Mark Miller, https://tekkie.wordpress.com

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“We need to do away with the myth that computer science is about computers. Computer science is no more about computers than astronomy is about telescopes, biology is about microscopes or chemistry is about beakers and test tubes. Science is not about tools, it is about how we use them and what we find out when we do.”
— “SIGACT trying to get children excited about CS,”
by Michael R. Fellows and Ian Parberry

There have been many times where I’ve thought about writing about this over the years, but I’ve felt like I’m not sure what I’m doing yet, or what I’m learning. So I’ve held off. I feel like I’ve reached a point now where some things have become clear, and I can finally talk about them coherently.

I’d like to explain some things that I doubt most CS students are going to learn in school, but they should, drawing from my own experience.

First, some notions about science.

Science is not just a body of knowledge (though that is an important part of it). It is also venturing into the unknown, and developing the idea within yourself about what it means to really know something, and to understand that knowing something doesn’t mean you know the truth. It means you have a pretty good idea of what the reality of what you are studying is like. You are able to create a description that somehow resembles the reality of what you’re studying to such a degree that you are able to make predictions about it, and those predictions can be confirmed within some boundaries that are either known, or can be discovered, and subsequently confirmed by others without the need to revise the model. Even then, what you have is not “the truth.” What you have might be a pretty good idea for the time being. As Richard Feynman said, in science you never really know if you are right. All you can be certain of is that you are wrong. Being wrong can be very valuable, because you can learn the limits of your common sense perceptions, and knowing that, direct your efforts towards what is more accurate, what is closer to reality.

The field of computing and computer science doesn’t have this perspective. It is not science. My CS professors used to admit this openly, but my understanding is CS professors these days aren’t even aware of this distinction anymore. In other words, they don’t know what science is, but they presume that what they practice is science. CS, as it’s taught, has some value, but what I hope to introduce people to here is the notion that after they have graduated with a CS degree, they are in kindergarten, or perhaps first grade. They have learned some basics about how to read and write, but they have not learned what is really powerful about that skill. I will share some knowledge I have gleaned as someone who has ventured as a beginner in this perspective.

The first thing to understand is that an undergraduate computer science education doesn’t tend to give you any notions about what computing is. It doesn’t explore models of computing, and in many cases, it doesn’t even present much in the way of different models of programming. It presents one model of computing (the Von Neumann model), but it doesn’t venture deeply into concepts of how the model works. It provides some descriptions of entities that are supposed to make it work, but it doesn’t tie them together so that you can see the relationships; see how the thing really works.

Science is about challenging and forming models of phenomena. A more powerful notion of computing is realized by understanding that the point of computer science is not about the application of computing to problems, but about creating, criticizing, and studying the strengths and weaknesses of different models of computing systems, and that programming is a means of modeling our ideas about them. In other words, programming languages and development environments can be used to model, explore, and test, and criticize our notions about different computing system models. It behooves the computer scientist to either choose an existing computing architecture represented by an existing language, or to create a new architecture, and a new language, that is suitable to what is being attempted, so that the focus can be maintained on what is being modeled, and testing that model without a lot of distraction.

As Alan Kay has said, the “language” part of “programming language” is really a user interface. I suggest that it is a user interface to a model of computing, a computing architecture. We can call it a programming model. As such, it presents a simulated environment of what is actually being accomplished in real terms, which enables a certain way of seeing the model you are trying to construct. (As I said earlier, we can use programming (with a language) to model our notions of computing.) In other words, you can get out of dealing with the guts of a certain computing architecture, because the runtime is handling those details for you. You’re just dealing with the interface to it. In this case, you’re using, quite explicitly, the architecture embodied in the runtime, not an API, as a means to an end. The power doesn’t lie in an API. The power you’re seeking to exploit is the architecture represented by the language runtime (a computing model).

This may sound like a confusing round-about, but what I’m saying is you can use a model of computing as a means for defining a new model of computing, whatever best suits the task. I propose that, indeed, that’s what we should be doing in computer science, if we’re not working directly with hardware.

When I talk about modeling computing systems, given their complexity, I’ve come to understand that constructing them is a gradual process of building up more succinct expressions of meaning for complex processes, with a goal of maintaining flexibility, in terms of how sub-processes that are used for higher levels of meaning can be used. As a beginner, I’ve found that starting with a powerful programming language in a minimalist configuration, with just basic primitives, was very constructive for understanding this, because it forced me to venture into constructing my own means for expressing what I want to model, and to understand what is involved in doing that. I’ve been using a version of Lisp for this purpose, and it’s been a very rewarding experience, but other students may have other preferences. I don’t mean to prejudice anyone toward one programming model. I recommend finding, or creating one that fits the kind of modeling you are pursuing.

Along with this perspective, I think, there must come an understanding of what different programming languages are really doing for you, in their fundamental architecture. What are the fundamental types in the language, and for what are they best suited? What are the constructs and facilities in the language, and what do they facilitate, in real terms? Sure, you can use them in all sorts of different ways, but to what do they lend themselves most easily? What are the fundamental functions in the runtime architecture that are experienced in the use of different features in the language? And finally, how are these things useful to you in creating the model you want to attempt? Seeing programming languages in this way provides a whole new perspective on them that has you evaluating how they facilitate your modeling practice.

Application comes along eventually, but it comes late in the process. The real point is to create the supporting architecture, and any necessary operating systems first. That’s the “hypothesis” in the science you are pursuing. Applications are tests of that hypothesis, to see if what is predicted by its creators actually bears out. The point is to develop hypotheses of computing systems so that their predictive limits can be ascertained, if they are not falsified. People will ask, “Where does practical application come in?” For the computer scientist involved in this process, it doesn’t, really. Engineers can plumb the knowledge base that’s generated through this process to develop ideas for better system software, software development systems, and application environments to deploy. However, computer science should not be in service to that goal. It can merely be useful toward it, if engineers see that it is fit to do so. The point is to explore, test, discuss, criticize, and strive to know.

These are just some preliminary thoughts on computer systems modeling. In my research, I’ve gotten indications that it’s not healthy for the discipline to be insular, just looking at its own artifacts for inspiration for new ideas. It needs to look at other fields of study to introduce unorthodox models into the discussion. I haven’t gotten into that yet. I’m still trying to understand some basic ideas of a computer system, using a more mathematical approach.

Related post: Does computer science have a future?

— Mark Miller, https://tekkie.wordpress.com

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In my time on Quora.com, I’ve answered a bunch of questions on object-oriented programming (OOP). In giving my answers, I’ve tried my best to hew as closely as I can to what I’ve understood of Alan Kay’s older notion of OOP from Smalltalk. The theme of most of them is, “What you think is OOP is not OOP.” I did this partly because it’s what’s most familiar to me, and partly because writing about it helped me think clearer thoughts about this older notion. I hoped that other Quora readers would be jostled out of their sense of complacency about OO architecture, and it seems I succeeded in doing that with a few of them. I’ve had the thought recently that I should share some of my answers on this topic with readers on here, since they are more specific descriptions than what I’ve shared previously. I’ve linked to these answers below (they are titled as the questions to which I responded).

What is Alan Kay’s definition of object-oriented? (Quora member Andrea Ferro had a good answer to this as well.)

A big thing I realized while writing this answer is that Kay’s notion of OOP doesn’t really have to do with a specific programming language, or a programming “paradigm.” As I said in my answer, it’s a method of system organization. One can use an object-oriented methodology in setting up a server farm. It’s just that Kay has used the same idea in isolating and localizing code, and setting up a system of communication within an operating system.

Another idea that had been creeping into my brain as I answered questions on OOP is that his notion of interfaces was really an abstraction. Interfaces were the true types in his message passing notion of OOP, and interfaces can and should span classes. So, types were supposed to span classes as well! The image that came to mind is that interfaces can be thought to sit between communicating objects. Messages, in a sense, pass through them, to dispatch logic in the receiving object, which then determines what actual functionality is executed as a result. Even the concept of behavior is an abstraction, a step removed from classes, because the whole idea of interfaces is that you can change the class that carries out a behavior with a completely new implementation (supporting the same interface), and the expected behavior for it will be exactly the same. In one of my answers I said that objects in OOP “emulate” behavior. That word choice was deliberate.

This seemed to finally make more sense for me than it ever had before about why Kay said that OOP is about what goes on between objects, not what goes on with the objects themselves (which are just endpoints for messages). The abstraction is interstitial, in the messaging (which is passed between objects), and the interfaces.

This is a conceptual description. The way interfaces were implemented in Smalltalk were as collections of methods in classes. They were strictly a “gentleman’s agreement,” both in terms of the messages to which they matched, and their behavior. They did not have any sort of type identifiers, except for programmers recognizing a collection of method headers (and their concomitant behaviors) as an interface.

Are utility classes good OO design?

Object-Oriented Programming: In layman’s terms, what is the difference between abstraction, encapsulation and information hiding?

What is the philosophical genesis of object-oriented programming methodology?

Why are C# and Java not considered as Object Oriented Language compared to the original concept by Alan Kay?

The above answer also applies to C++.

What does Alan Kay mean when he said: “OOP to me means only messaging, local retention and protection and hiding of state-process, and extreme late-binding of all things. It can be done in Smalltalk and in LISP”?

What does Darwin’s theory of evolution bring to object oriented programming methodology?

This last answer gets to what I think are some really interesting thoughts that one can have about OOP. I posted a video in my answer from a presentation by philosopher Daniel Dennet on “Free Will Determinism and Evolution.” Dennet takes an interesting approach to philosophy. He seems almost like a scientist, but not quite. In this presentation, he uses Conway’s game of “life” to illustrate a point about free will in complex, very, very, very large scale systems. He proposes a theory that determinism is necessary for free will (not contrary to it), and that as systems survive, evolve, and grow, free will becomes more and more possible, whereby multiple systems that are given the same inputs will make different decisions (once they reach a structured complexity that makes it possible for them to make what could be called  “decisions”). I got the distinct impression after watching this that this idea has implications for where object-orientation can go in the direction of artificial intelligence. It’s hard for me to say what this would require of objects, though.

—Mark Miller, https://tekkie.wordpress.com

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This presentation by Bret Victor could alternately be called “Back To The Future,” but he called it, “The Future of Programming.” What’s striking is this is still a possible future for programming, though it was all really conceivable back in 1973, the time period in which Bret set it.

I found this video through Mark Guzdial. It is the best presentation on programming and computing I’ve seen since I’ve watched what Alan Kay has had to say on the subject. Bret did a “time machine” performance set in 1973 on what was accomplished by some great engineers working on computers in the 1960s and ’70s, and generally what those accomplishments meant to computing. I’ve covered some of this history in my post “A history lesson in government R&D, Part 2,” though I de-emphasized the programming aspect.

Bret posed as someone who was presenting new information in 1973 (complete with faux overhead projector), and someone who tried to predict what the future of programming and computing would be like, given these accomplishments, and reasoning about the future, if what was then-current thinking progressed.

The main theme, which has been a bit of a revelation to me recently, is this idea of programming being an exercise in telling the computer what you want, and having the computer figure out how to deliver it, and even computers figuring out how to get what they need from each other, without the programmer having to spell out how to do these things step by step. What Bret’s presentation suggested to me is that one approach to doing this is having a library of “solvers,” operating under a set of principles (or perhaps a single principle), that the computing system can invoke at any time, in a number of combinations, in an attempt to accomplish that goal; that operational parameters are not fixed, but relatively fluid.

Alan Kay talked about Licklider’s idea of “communicating with aliens,” and how this relates to computing, in this presentation he gave at SRII a couple years ago. A “feature” of many of Alan’s videos is that you don’t get to see the slides he’s showing…which can make it difficult to follow what he’s talking about. So I’ll provide a couple reference points. At about 17 minutes in “this guy” he’s talking about is Licklider, and a paper he wrote called “Man-Computer Symbiosis.” At about 44 minutes in I believe Alan is talking about the Smalltalk programming environment.


I happened to find this from “The Dream Machine,” by M. Mitchell Waldrop, as well, sourced from an article written by J.C.R. Licklider and Robert Taylor called, “The Computer as a Communication Device,” in a publication called “Science & Technology” in 1968, also reprinted in “In Memoriam: J.C.R. Licklider, 1915-1990,” published in Digital Systems Research Center Reports, vol. 61, 1990:

“Modeling, we believe, is basic and central to communications.” Conversely, he and Taylor continued, “[a successful communication] we now define concisely as ‘cooperative modeling’–cooperation in the construction, maintenance, and use of a model. [Indeed], when people communicate face to face, they externalize their models so they can be sure they are talking about the same thing. Even such a simple externalized model as a flow diagram or an outline–because it can be seen by all the communicators–serves as a focus for discussion. It changes the nature of communication: When communicators have no such common framework, they merely make speeches at each other; but when they have a manipulable model before them, they utter a few words, point, sketch, nod, or object.”

I remember many years ago hearing Alan Kay say that what’s happened in computing since the 1970s “has not been that exciting.” Bret Victor ably justified that sentiment. What he got across (to me, anyway) was a sense of tragedy that the thinking of the time did not propagate and progress from there. Academic computer science, and the computer industry acted as if this knowledge barely existed. The greater potential tragedy Bret expressed was, “What if this knowledge was forgotten?”

The very end of Bret’s presentation made me think of Bob Barton, a man that Alan has sometimes referred to when talking about this subject. Barton was someone who Alan seemed very grateful to have met as a graduate student, because he disabused the computer science students at the University of Utah in their notions of what computing was. Alan said that Barton freed their minds on the subject, which opened up a world of possibilities that they could not previously see. In a way Bret tried to do the same thing by leaving the ending of his presentation open-ended. He did not say that meta-programming “is the future,” just one really interesting idea that was developed decades ago. Many people in the field think they know what computing and programming are, but these are still unanswered questions. I’d add to that message that what’s needed is a spirit of adventure and exploration. Like our predecessors, we’ll find some really interesting answers along the way which will be picked up by others and incorporated into the devices the public uses, as happened before.

I hope that students just entering computer science will see this and carry the ideas from it with them as they go through their academic program. What Bret presents is a perspective on computer science that is not shared by much of academic CS today, but if CS is to be revitalized one thing it needs to do is “get” what this perspective means, and why it has value. I believe it is the perspective of a real computer scientist.

Related post: Does computer science have a future?

—Mark Miller, https://tekkie.wordpress.com

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I came across this interview with Lesley Chilcott, the producer of “An Inconvenient Truth” and “Waiting For Superman.” Kind of extending her emphasis on improving education, she produced a short 9-minute video selling the idea of “You should learn to code,” both to adults and children. It addresses two points: 1) the anticipated shortage of programmers needed to write software in the future, and 2) the increasing ubiquity of programming in all sorts of fields where people would think it wouldn’t exist, such as manufacturing and agriculture.

The interview gets interesting at 3 minutes 45 seconds in.

Michelle Fields, the interviewer, asked what I thought were some insightful questions. She started things off with:

It seems as though the next generation is so fluent in technology. How is it that they don’t know what computer programming is?

Chilcott said:

I think the reason is, you know, we all use technology every day. It’s surrounding us. Like, we can debate the pro’s and con’s of technology/social media, but the bottom line is it’s everywhere, right? So I think a lot of people know how to read it. They grow up playing with an iPhone or something like that, but they don’t know how to write it. And so when you say, “Do you know what this is,” specifically, or what this job is–and you know, those kids are in first, second, fifth grade–they know all about it, but they don’t know what the job is.

I found this answer confusing. She’s kind of on the right track, thinking of programming as “writing.” I cut her some slack, because as she admits in the interview, she’s just started programming herself. However, as I’ve said before, running software is not “reading.” It’s really more like being read to by a machine, like listening to an audio book, or someone else reading to you. You don’t have to worry about the mental tasks of pronunciation, sentence construction, or punctuation. You can just listen to the story. Running software doesn’t communicate the process that the code is generating, because there’s a lot that the person using it is not shown. This is on purpose, because most people use software to accomplish some utilitarian task unrelated to how a computer works. They’re not using it to understand a process.

The last sentence came across as muddled. I think what she meant was they know all about using technology, but they don’t know how to create it (“what the job is”).

Fields then asked,

There was this study which found that 56% of students would rather eat broccoli than learn math. Do you think that since computer programming is somewhat related to math, that that’s the reason children and students shy away from it?

Chilcott said:

It could be. That is one of the myths that exist. There is some, you know, math, but as Bill Gates and some other people said, you know, addition, subtraction–It’s much more about problem solving, and I think people like to problem-solve, they like mysteries, they like decoding things. It’s much more about that than complicated algorithms.

She’s right that there is problem solving involved with programming, but she’s either mistaken or confusing math with arithmetic when she says that the relationship between math and programming is a “myth.” I can understand why she tries to wave it off, because as Fields pointed out, most students don’t like math. I contend, as do some mathematicians, this is due to the way it’s taught in our schools. The essence of math gets lost. Instead it’s presented as a tool for calculation, and possibly a cognitive development discipline for problem solving, both of which don’t communicate what it really is, and remove a lot of its beauty.

In reality math is pervasive in programming, but to understand why I say this you have to understand that math is not arithmetic–addition, subtraction, like she suggests. This confusion is common in our society. I talk more about this here. Having said this, it does not mean that programming is hard right off the bat. The math involved has more to do with logic and reasoning. I like the message in the video below from a couple of the programmers interviewed: “You don’t have to be a genius to know how to code. … Do you have to be a genius to do math? No.” I think that’s the right way to approach this. Math is important to programming, but it’s not just about calculating a result. While there’s some memorization, understanding a programming language’s rules, and knowing what different things are called, that’s not a big part of it.

The cool thing is you can accomplish some simple things in programming, to get started, without worrying about math at all. It becomes more important if you want to write complex programs, but that’s something that can wait.

My current understanding is the math in programming is about understanding the rules of a system and what statements used in that system imply, and then understanding the effects of those implications. That sounds complicated, but it’s just something that has to be learned to do anything significant with programming, and once learned will become more and more natural. I liken it to understanding how to drive a car on the road. You don’t have to learn this concept right away, though. When first starting out, you can just look at and enjoy the effects of trying out different things, exploring what a programming environment offers you.

Where Chilcott shines in the interview above is when she becomes the “organizer.” She said that even though 95% of the schools have computers and internet access, only 10% have what she calls a “computer science” course. (I wish they’d go back to calling it a “programming course.” Computer science is more than what most of these schools teach, but I’m being nit-picky.) The cool thing about Code.org, a web site she promotes, is that it tries to locate a school near you that offers programming courses. If there aren’t any, no problem. You can learn some basics of programming right inside your browser using the online tools that it offers on the site.

The video Chilcott produced is called “Code Stars” in the above interview, but when I went looking for it I found it under the name “the Code.org film,” or, “What Most Schools Don’t Teach.”

Here is the full 9-minute video:

If you want the shorter videos, you can find them here.

The programming environment you see kids using in these videos is called “Scratch.”

Gabe Newell said of programming:

When you’re programming, you’re teaching possibly the stupidest thing in the entire universe–a computer–how to do something.

I see where Newell is going with this, but from my perspective it depends on what programming environment you’re using. Some programming languages have the feel of you “teaching” the system when you’re programming. Others have the feel of creating relationships between simple behaviors. Others, still, have the feel of using relationships to set up rules for a new system. Programming comes in a variety of approaches. However, the basic idea that Newell gets across is true, that computers only come with a set of simple operations, and that’s it. They don’t do very much by themselves, or even in combination. It’s important for those new to programming to learn this early on. Some of my early experiences in programming match those of new programmers even today. One of them is, when using a programming language, one is tempted to assume that the computer will infer the meaning of some programming expression from context. There is some context used in programming, but not much, and it’s highly formalized. It’s not intuitive. I can remember the first time I learned this it was like the joke where, say, someone introduces his/her friend to a dumb, witless character in a skit. He/she says, “Say hi to my friend, Frank,” and the dummy says, “Hi to my friend Frank.” And the guy/gal says, “NO! I mean…say hello,” making a hand gesture trying to get the two to connect, and the dummy might look at the friend and say, “Hello,” but that’s it. That’s kind of a realization to new programmers. Yeah, the computer has to have almost everything explained to it (or modeled), even things we do without thinking about it. It’s up to the programmer to make the connections between the few things the computer knows how to do, to make something larger happen.

Jack Dorsey talked about programming in a way that I think is important. His ultimate goal when he started out was to model something, and make the model malleable enough that he could manipulate it, because he wanted to use it for understanding how cities work.

Bill Gates emphasized control. This is a common early motivation for programmers. Not necessarily controlling people, but controlling the computer. What Gates was talking about was what I’d call “making your own world,” like Dorsey was saying, but he wanted to make it real. When I was in high school (late 1980s) it was a rather common project for aspiring programming students to create “matchmaking” programs, where boys and girls in the whole school would answer a simple questionnaire, and a computer program that a student had written would try to match them up by interests, not unlike some of the online dating sites that are out there now. I never heard of any students finding their true love through one of these projects, but it was fun for some people.

Vanessa Hurst said, “You don’t have to be a genius to know how to code. You need to be determined.” That’s pretty much it in a nutshell. In my experience everything else flowed from determination when I was learning how to do this. It will drive you to learn what you need to learn to get it, even if sometimes it’s subject matter you find tedious and icky. You learn to just push through it to get to the glorious feeling at the end of having accomplished what you set out to do.

Newell said at the end of the video,

The programmers of tomorrow are the wizards of the future. You’re going to look like you have magic powers compared to everybody else.

That’s true, but this has been true for a long time. In my professional work developing custom database solutions for business customers I had the experience of being viewed like a magician, because customers didn’t know how I did what I did. They just appreciated the fact that I could do it. I really don’t mean to discourage anyone, because I still enjoy programming today, and I want to encourage people to learn programming, but I feel the need to say something, because I don’t want people to get disillusioned over this. This status of “wizard,” or “magician” is not always what it’s cracked up to be. It can feel great, but there is a flip side to it that can be downright frustrating. This is because people who don’t know a wit of what you know how to do can get confused about what your true abilities are, and they can develop unrealistic expectations of you. I’ve found that wherever possible, the most pleasurable work environment is working among those who also know how to code, because we’re able to size each other up, and assign tasks appropriately. I encourage those who are pursuing software development as a career to shoot for that.

A couple things I can say for being able to code are:

  • It makes you less of a “victim” in our technology world. Once you know how to do it, you have an idea about how other programs work, and the pitfalls they can fall into that might compromise your private information, allow a computer cracker to access it, or take control of your system. You don’t have to feel scared at the alarming “hacking” or phishing reports you hear on the news, because you can be choosey about what software you use based on how it was constructed, what it’s capable of, how much power it gives you (not someone else), and not just base a decision on the features it has, or cool graphics and promotion. You can become a discriminating user of software.
  • You gain the power to create the things that suite you. You don’t have to use software that you don’t like, or you think is being offered on unreasonable terms. You can create your own, and it can be whatever you want. It’s just a matter of the knowledge you’re willing to gather and the amount of energy you’re willing to put into developing the software.

Edit 5-20-2013: While I’m on this subject, I thought I should include this video by Mitch Resnick, who has been involved in creating Scratch at MIT. Similar to what Lesley Chilcott said above, he said, “It’s almost as if [users of new technologies] can read, but not write,” referring to how people use technology to interact. I disagreed with the notion, above, that using technology is the same as reading. Resnick hedged a bit on that. I can kind of understand why he might say this, because by running a Scratch program, it is like reading it, because you can see how code creates its results in the environment. This is not true, however, of much of the technology people use today.

Mark Guzdial asked a question a while back that I thought was important, because it brings this issue down to where a lot of people live. If the kind of literacy I’m going to talk about below is going to happen, the concept needs to be able to come down “out of the clouds” and become more pedestrian. Not to say that literacy needs to be watered down in toto (far from it), but that it should be possible to read and write to communicate everyday ideas and experiences without being super sophisticated about it. What Mark asked was, in the context of a computing medium, what would be the equivalent of a “note to grandma”? I remember suggesting Dan Ingalls’s prop-piston concept from his Lively Kernel demos as one candidate. Resnick provided what I thought were some other good ones, but in the context of Mother’s Day.

Context reversal

The challenge that faces new programmers today is different from when I learned programming as a child in one fundamental way. Today, kids are introduced to computers before they enter school. They’re just “around.” If you’ve got a cell phone, you’ve got a computer in your pocket. The technology kids use presents them with an easy-to-use interface, but the emphasis is on use, not authoring. There is so much software around it seems you can just wish for it, and it’s there. The motivation to get into programming has to be different than what motivated me.

When I was young the computer industry was still something new. It was not widespread. Most computers that were around were big mainframes that only corporations and universities could afford and manage. When the first microcomputers came out, there wasn’t much software for them. It was a lot easier to be motivated to learn programming, because if you didn’t write it, it probably didn’t exist, or it was too expensive to get (depending on your financial circumstances). The way computers operated was more technical than they are today. We didn’t have graphical user interfaces (at first). Everything was done from some kind of text command line interface that filled the entire screen. Every computer came with a programming language as well, along with a small manual giving you an introduction on how to use it.

PC-DOS, from Wikipedia

It was expected that if you bought a computer you’d learn something about programming it, even if it was just a little scripting. Sometimes the line between what was the operating system’s command line interface, and what was the programming language was blurred. So even if all you wanted to do was manipulate files and run programs, you were learning a little about programming just by learning how to use the computer. Some of today’s software developers came out of that era (including yours truly).

Computer and operating system manufacturers had stopped including programming languages with their systems by the mid-1990s. Programming languages had also been taken over by professionals. The typical languages used by developers were much harder to learn for beginners. There were educational languages around, but they had fallen behind the times. They were designed for older personal computer systems, and when the systems got more sophisticated no one had come around to update them. That began to be remedied only in the last 10 years.

Computer science was still a popular major at universities in the 1990s, due to the dot-com craze. When that bubble burst in 2000, that went away, too. So in the last 18 years we’ve had what I’d call an “educational programming winter.” Maybe we’ll see a revival. I hope so.

Literacy reconsidered

I’m directing the rest of this post to educators, because there are some issues around a programming revival I’d like to address. I’m going to share some more detailed history, and other perspectives on computer programming.

What many may not know is that we as a society have already gone through this once. From the late 1970s to the mid-1980s there was a major push to teach programming in schools as “computer literacy.” This was the regime that I went through. The problem was some mistakes were made, and this caused the educational movement behind it to collapse. I think the reason this happened was due to a misunderstanding of what’s powerful about programming, and I’d like educators to evaluate their current thinking in light of this, so that hopefully they do not repeat the mistakes of the past.

As I go through this part, I’ll mostly be quoting from a Ph.D. thesis written by John Maxwell in 2006 called Tracing the Dynabook: A Study of Technocultural Transformations.” (h/t Bill Kerr)

Back in the late 1970s microcomputers/personal computers were taking off like wildfire with Apple II’s, and Commodore VIC-20’s, and later, Commodore 64’s, and IBM PCs. They were seen as “the future.” Parents didn’t want their children to be “left behind” as “technological illiterates.” This was the first time computers were being brought into the home. It was also the first time many schools were able to grant students access to computers.

Educators thought about the “benefits” of using a computer for certain cognitive and social skills.  Programming spread in public school systems as something to teach students. Fred D’Ignazio wrote in an article called “Beyond Computer Literacy,” from 1983:

A recent national “computers in the schools” survey conducted by the Center for the Social Organization of Schools at Johns Hopkins University found that most secondary schools are using computers to teach programming. … According to the survey, the second most popular use of computers was for drill and practice, primarily for math and language arts. In addition, the majority of the teachers who responded to the survey said that they looked at the computer as a “resource” rather than as a “tool.”

…Another recent survey (conducted by the University of Maryland) echoes the Johns Hopkins survey. It found that most schools introduce computers into the curriculum to help students become literate in computer technology. But what does this literacy entail?

Because of the pervasive spread of computers throughout our society, we have all become convinced that computers are important. From what we read and hear, when our kids grow up almost everyone will have to use computers in some aspect of their lives. This makes computers, as a subject, not only important, but also relevant.

An important, relevant subject like computers should be part of a school’s curriculum. The question is how “Computers” ought to be taught.

Special computer classes are being set up so that students can play with computers, tinker with them, and learn some basic programming. Thus, on a practical level, computer literacy turns out to be mere computer exposure.

But exposure to what? Kids who are now enrolled in elementary and secondary schools are exposed to four aspects of computers. They learn that computers are programmable machines. They learn that computers are being used in all areas of society. They learn that computers make good electronic textbooks. And (something they already knew), they learn that computers are terrific game machines.

… According to the surveys, real educational results have been realized at schools which concentrate on exposing kids to computers. … Kids get to touch computers, play with them, push their buttons, order them about, and cope with computers’ incredible dumbness, their awful pickiness, their exasperating bugs, and their ridiculous quirks.

The main benefits D’Ignazio noted were ancillary. Students stayed at school longer, came in earlier, and stayed late. They were more attentive to their studies, and the computers fostered a sense of community, rather than competition and rivalry. If you read his article, you get a sense that there was almost a “worship” of computers on the part of educators. They didn’t understand what they were, or what they represented, but they were so interesting! There’s a problem there… When people are fascinated by something they don’t understand, they tend to impose meanings on it that are not backed by evidence, and so miss the point. The mistaken perceptions can be strengthened by anecdotal evidence (one of the weakest kinds). This is what happened to programming in schools.

The success of the strategy of using computers to try to improve higher-order thinking was illusory. John Maxwell’s telling of the “life and death of Logo” (my phrasing) serves as a useful analog to what happened to programming in schools generally. For those unfamiliar with it, the basic concept of Logo was a programming environment in which the student manipulates an object called a “turtle” via. commands. The student can ask the turtle to rotate and move. As it moves it drags a pen behind it, tracing its trail.  Other versions of this language were created that allowed more capabilities, allowing further exploration of the concepts for which it was created. The original idea Seymour Papert, who taught children using Logo, had was to teach young children about sophisticated math concepts, but our educational system imposed a very different definition and purpose on it. Just because something is created on a computer with the intent of it being used for a specific purpose doesn’t mean that others can’t use it for completely different, and possibly less valuable purposes. We’ve seen this a lot with computers over the years; people “misusing” them for both constructive and destructive ends.

As I go forward with this, I just want to put out a disclaimer that I don’t have answers to the problems I point out here. I point them out to make people aware of them, to get people to pause with the pursuit of putting people through this again, and to point to some people who are working on trying to find some answers. I present some of their learned opinions. I encourage interested readers to read up on what these people have had to say about the use of computers in education, and perhaps contact them with the idea of learning more about what they’ve found out.

I ask the reader to pay particular attention to the “benefits” that educators imposed on the idea of programming during this period that Maxwell talks about, via. what Papert called “technocentrism.” You hear this being echoed in the videos above. As you go through this, I also want you to notice that Papert, and another educator by the name of Alan Kay, who have thought a lot about what computers represent, have a very different idea about the importance of computers and programming than is typical in our school system, and in the computer industry.

The spark that started Logo’s rise in the educational establishment was the publication of Papert’s book, “Mindstorms: Children, Computers, and Powerful Ideas” in 1980. Through the process of Logo’s promotion…

Logo became in the marketplace (in the broad sense of the word) [a] particular black box: turtle geometry; the notion that computer programming encourages a particular kind of thinking; that programming in Logo somehow symbolizes “computer literacy.” These notions are all very dubious—Logo is capable of vastly more than turtle graphics; the “thinking skills” strategy was never part of Papert’s vocabulary; and to equate a particular activity like Logo programming with computer literacy is the equivalent of saying that (English) literacy can be reduced to reading newspaper articles—but these are the terms by which Logo became a mass phenomenon.

It was perhaps inevitable, as Papert himself notes (1987), that after such unrestrained enthusiasm, there would come a backlash. It was also perhaps inevitable given the weight that was put on it: Logo had come, within educational circles, to represent computer programming in the large, despite Papert’s frequent and eloquent statements about Logo’s role as an epistemological resource for thinking about mathematics. [my emphasis — Mark] In the spirit of the larger project of cultural history that I am attempting here, I want to keep the emphasis on what Logo represented to various constituencies, rather than appealing to a body of literature that reported how Logo “didn’t work as promised,” as many have done (e.g., Sloan 1985; Pea & Sheingold 1987). The latter, I believe, can only be evaluated in terms of this cultural history. Papert indeed found himself searching for higher ground, as he accused Logo’s growing numbers of critics of technocentrism:

“Egocentrism for Piaget does not mean ‘selfishness’—it means that the child has difficulty understanding anything independently of the self. Technocentrism refers to the tendency to give a similar centrality to a technical object—for example computers or Logo. This tendency shows up in questions like ‘What is THE effect of THE computer on cognitive development?’ or ‘Does Logo work?’ … such turns of phrase often betray a tendency to think of ‘computers’ and ‘Logo’ as agents that act directly on thinking and learning; they betray a tendency to reduce what are really the most important components of educational situations—people and cultures—to a secondary, faciltiating role. The context for human development is always a culture, never an isolated technology.”

But by 1990, the damage was done: Logo’s image became that of a has-been technology, and its black boxes closed: in a 1996 framing of the field of educational technology, Timothy Koschmann named “Logo-as-Latin” a past paradigm of educational computing. The blunt idea that “programming” was an activity which could lead to “higher order thinking skills” (or not, as it were) had obviated Papert’s rich and subtle vision of an ego-syntonic mathematics.

By the early 1990s … Logo—and with it, programming—had faded.

The message–or black box–resulting from the rise and fall of Logo seems to have been the notion that “programming” is over-rated and esoteric, more properly relegated to the ash-heap of ed-tech history, just as in the analogy with Latin. (pp. 183-185)

To be clear, the last part of the quote refers only to the educational value placed on programming by our school system. When educators attempted to formally study and evaluate programming’s benefits on higher-order thinking and the like, they found it wanting, and so most schools gradually dropped teaching programming in the 1990s.

Maxwell addresses the conundrum of computing and programming in schools, and I think what he says is important to consider as people try to “reboot” programming in education:

[The] critical faculties of the educational establishment, which we might at least hope to have some agency in the face of large-scale corporate movement, tend to actually disengage with the critical questions (e.g., what are we trying to do here?) and retreat to a reactionary ‘humanist’ stance in which a shallow Luddism becomes a point of pride. Enter the twin bogeymen of instrumentalism and technological determinism: the instrumentalist critique runs along the lines of “the technology must be in the service of the educational objectives and not the other way around.” The determinist critique, in turn, says, ‘the use of computers encourages a mechanistic way of thinking that is a danger to natural/human/traditional ways of life’ (for variations, see, Davy 1985; Sloan 1985; Oppenheimer 1997; Bowers 2000).

Missing from either version of this critique is any idea that digital information technology might present something worth actually engaging with. De Castell, Bryson & Jenson write:

“Like an endlessly rehearsed mantra, we hear that what is essential for the implementation and integration of technology in the classroom is that teachers should become ‘comfortable’ using it. […] We have a master code capable of utilizing in one platform what have for the entire history of our species thus far been irreducibly different kinds of things–writing and speech, images and sound–every conceivable form of information can now be combined with every other kind to create a different form of communication, and what we seek is comfort and familiarity?”

Surely the power of education is transformation. And yet, given a potentially transformative situation, we seek to constrain the process, managerially, structurally, pedagogically, and philosophically, so that no transformation is possible. To be sure, this makes marketing so much easier. And so we preserve the divide between ‘expert’ and ‘end-user;’ for the ‘end-user’ is profoundly she who is unchanged, uninitiated, unempowered.

A seemingly endless literature describes study after study, project after project, trying to identify what really ‘works’ or what the critical intercepts are or what the necessary combination of ingredients might be (support, training, mentoring, instructional design, and so on); what remains is at least as strong a body of literature which suggests that this is all a waste of time.

But what is really at issue is not implementation or training or support or any of the myriad factors arising in discussions of why computers in schools don’t amount to much. What is really wrong with computers in education is that for the most part, we lack any clear sense of what to do with them, or what they might be good for. This may seem like an extreme claim, given the amount of energy and time expended, but the record to date seems to support it. If all we had are empirical studies that report on success rates and student performance, we would all be compelled to throw the computers out the window and get on with other things.

But clearly, it would be inane to try to claim that computing technology–one of the most influential defining forces in Western culture of our day, and which shows no signs of slowing down–has no place in education. We are left with a dilemma that I am sure every intellectually honest researcher in the field has had to consider: we know this stuff is important, but we don’t really understand how. And so what shall we do, right now?

It is not that there haven’t been (numerous) answers to this question. But we have tended to leave them behind with each surge of forward momentum, each innovative push, each new educational technology “paradigm” as Timothy Koschmann put it. (pp. 18-19)

The answer is not a “reboot” of programming, but rather a rethinking of it. Maxwell makes a humble suggestion: that educators stop being blinded by “the shiny new thing,” or some so-called “new” idea such that they lose their ability to think clearly about what’s being done with regard to computers in education, and that they deal with history and historicism. He said that the technology field has had a problem with its own history, and this tends to bleed over into how educators regard it. The tendency is to forget the past, and to downplay it (“That was neat then, but it’s irrelevant now”).

In my experience, people have associated technology’s past with memories of using it. They’ve given little if any thought to what it represented. They take for granted what it enabled them to do, and do not consider what that meant. Maxwell said that this…

…makes it difficult, if not impossible, to make sense of the role of technology in education, in society, and in politics. We are faced with a tangle of hobbles–instrumentalism, ahistoricism, fear of transformation, Snow’s “two cultures,” and a consumerist subjectivity.

An examination of the history of educational technology–and educational computing in particular–reveals riches that have been quite forgotten. There is, for instance, far more richness and depth in Papert’s philosophy and his more than two decades of practical work on Logo than is commonly remembered. And Papert is not the only one. (p. 20)

Maxwell went into what Alan Kay thought about the subject. Kay has spent almost as many years as Papert working on a meaningful context for computing and programming within education. Some of the quotes Maxwell uses are from “The Early History of Smalltalk,” (h/t Bill Kerr) which I’ll also refer to. The other sources for Kay’s quotes are included in Maxwell’s bibliography:

What is Literacy?

“The music is not in the piano.” — Alan Kay

The past three or four decades are littered with attempts to define “computer literacy” or something like it. I think that, in the best cases, at least, most of these have been attempts to establish some sort of conceptual clarity on what is good and worthwhile about computing. But none of them have won large numbers of supporters across the board.

Kay’s appeal to the historical evolution of what literacy has meant over the past few hundred years is, I think, a much more fruitful framing. His argument is thus not for computer literacy per se, but for systems literacy, of which computing is a key part.

That this is a massive undertaking is clear … and the size of the challenge is not lost on Kay. Reflecting on the difficulties they faced in trying to teach programming to children at PARC in the 1970s, he wrote that:

“The connection to literacy was painfully clear. It is not just enough to learn to read and write. There is also a literature that renders ideas. Language is used to read and write about them, but at some point the organization of ideas starts to dominate the mere language abilities. And it helps greatly to have some powerful ideas under one’s belt to better acquire more powerful ideas.”

Because literature is about ideas, Kay connects the notion of literacy firmly to literature:

“What is literature about? Literature is a conversation in writing about important ideas. That’s why Euclid’s Elements and Newton’s Principia Mathematica are as much a part of the Western world’s tradition of great books as Plato’s Dialogues. But somehow we’ve come to think of science and mathematics as being apart from literature.”

There are echoes here of Papert’s lament about mathophobia, not fear of math, but the fear of learning that underlies C.P. Snow’s “two cultures,” and which surely underlies our society’s love-hate relationship with computing. Kay’s warning that too few of us are truly fluent with the ways of thinking that have shaped the modern world finds an anchor here. How is it that Euclid and Newton, to take Kay’s favourite examples, are not part of the canon, unless one’s very particular scholarly path leads there? We might argue that we all inherit Euclid’s and Newton’s ideas, but in distilled form. But this misses something important … Kay makes this point with respect to Papert’s experiences with Logo in classrooms:

“Despite many compelling presentations and demonstrations of Logo, elementary school teachers had little or no idea what calculus was or how to go about teaching real mathematics to children in a way that illuminates how we think about mathematics and how mathematics relates to the real world.” (Maxwell, pp. 135-137)

Just a note of clarification: I refer back to what Maxwell said re. Logo and mathematics. Papert did not use his language to teach programming as an end in itself. His goal was to use a computer to teach mathematics to children. Programming with Logo was the means for doing it. This is an important concept to keep in mind as one considers what role computer programming plays in education.

The problem, in Kay’s portrayal, isn’t “computer literacy,” it’s a larger one of familiarity and fluency with the deeper intellectual content; not just that which is specific to math and science curriculum. Kay’s diagnosis runs very close to Neil Postman’s critiques of television and mass media … that we as a society have become incapable of dealing with complex issues.

“Being able to read a warning on a pill bottle or write about a summer vacation is not literacy and our society should not treat it so. Literacy, for example, is being able to fluently read and follow the 50-page argument in [Thomas] Paine’s Common Sense and being able (and happy) to fluently write a critique or defense of it.” (Maxwell, p. 137)

Extending this quote (from “The Early History of Smalltalk”), Kay went on to say:

Another kind of 20th century literacy is being able to hear about a new fatal contagious incurable disease and instantly know that a disastrous exponential relationship holds and early action is of the highest priority. Another kind of literacy would take citizens to their personal computers where they can fluently and without pain build a systems simulation of the disease to use as a comparison against further information.

At the liberal arts level we would expect that connections between each of the fluencies would form truly powerful metaphors for considering ideas in the light of others.

Continuing with Maxwell (and Kay):

“Many adults, especially politicians, have no sense of exponential progressions such as population growth, epidemics like AIDS, or even compound interest on their credit cards. In contrast, a 12-year-old child in a few lines of Logo […] can easily describe and graphically simulate the interaction of any number of bodies, or create and experience first-hand the swift exponential progressions of an epidemic. Speculations about weighty matters that would ordinarily be consigned to common sense (the worst of all reasoning methods), can now be tried out with a modest amount of effort.”

Surely this is far-fetched; but why does this seem so beyond our reach? Is this not precisely the point of traditional science education? We have enough trouble coping with arguments presented in print, let alone simulations and modeling. Postman’s argument implicates television, but television is not a techno-deterministic anomaly within an otherwise sensible cultural milieu; rather it is a manifestation of a larger pattern. What is wrong here has as much to do with our relationship with print and other media as it does with television. Kay noted that “In America, printing has failed as a carrier of important ideas for most Americans.” To think of computers and new media as extensions of print media is a dangerous intellectual move to make; books, for all their obvious virtues (stability, economy, simplicity) make a real difference in the lives of only a small number of individuals, even in the Western world. Kay put it eloquently thus: “The computer really is the next great thing after the book. But as was also true with the book, most [people] are being left behind.” This is a sobering thought for those who advocate public access to digital resources and lament a “digital divide” along traditional socioeconomic lines. Kay notes,

“As my wife once remarked to Vice President Al Gore, the ‘haves and have-nots’ of the future will not be caused so much by being connected or not to the Internet, since most important content is already available in public libraries, free and open to all. The real haves and have-nots are those who have or have not acquired the discernment to search for and make use of high content wherever it may be found.” (Maxwell, pp. 138-139)

I’m still trying to understand myself what exactly Alan Kay means by “literature” in the realm of computing. He said that it is a means for discussing important ideas, but in the context of computing, what ideas? I suspect from what’s been said here he’s talking about what I’d call “model content,” thought forms, such as the idea of an exponential progression, or the concept of velocity and acceleration, which have been fashioned in science and mathematics to describe ideas and phenomena. “Literature,” as he defined it, is a means of discussing these thought forms–important ideas–in some meaningful context.

In prior years he had worked on that in his Squeak environment, working with some educators. They would show children a car moving across the screen, dropping dots as it went, illustrating velocity, and then, modifying the model, acceleration. Then they would show them Galileo’s experiment, dropping heavy and light balls from the roof of a building (real balls from a real building), recording the ball dropping, and allowing the children to view the video of the ball, and simultaneously model it via. programming, and discovering that the same principle of acceleration applied there as well. Thus, they could see in a couple contexts how the principle worked, how they could recognize it, and see its relationship to the real world. The idea being that they could grasp the concepts that make up the idea of acceleration, and then integrate it into their thinking about other important matters they would encounter in the future.

Maxwell quoted from an author named Andrew diSessa to get deeper into the concept of literacy, specifically what literacy in a type of media offers our understanding of issues:

The hidden metaphor behind transparency–that seeing is understanding–is at loggerheads with literacy. It is the opposite of how media make us smarter. Media don’t present an unadulterated “picture” of the problem we want to solve, but have their fundamental advantage in providing a different representation, with different emphases and different operational possibilities than “seeing and directly manipulating.”

What’s a good goal for computing?

The temptation in teaching and learning programming is to get students familiar enough with the concepts and a language that they can start creating things with it. But create what? The typical cases are to allow students to tinker, and/or to create applications which gradually become more complex and feature-rich, with the idea of building confidence and competence with increasing complexity. The latter is not a bad idea in itself, but listening to Alan Kay has led me to believe that starting off with this is the equivalent of jumping to a conclusion too quickly, and to miss the point of what’s powerful about computers and programming.

I like what Kay said in “The Early History of Smalltalk” about this:

A twentieth century problem is that technology has become too “easy.” When it was hard to do anything whether good or bad, enough time was taken so that the result was usually good. Now we can make things almost trivially, especially in software, but most of the designs are trivial as well. This is inverse vandalism: the making of things because you can. Couple this to even less sophisticated buyers and you have generated an exploitation marketplace similar to that set up for teenagers. A counter to this is to generate enormous dissatisfaction with one’s designs using the entire history of human art as a standard and goal. Then the trick is to decouple the dissatisfaction from self worth–otherwise it is either too depressing or one stops too soon with trivial results.

Edit 4-5-2013: I thought I should point out that this quote has some nuance to it that people might miss. I don’t believe Kay is saying that “programming should be hard.” Quite the contrary. One can observe from his designs that he’s advocated the opposite. Not that technology should mold itself to what is “natural” for humans. It might require some training and practice, but once mastered, it should magnify or enhance human capabilities, thereby making previously difficult or tedious tasks easier to accomplish and incorporate into a larger goal.

Kay was making an observation about the history of technology’s relationship to society, that the effect on people of useful technology being hard to build has generally caused the people who created something useful to make it well. What he’s pointing out is that people generally take the presence of technology as an excuse to use it as a crutch, in this case to make immediate use of it towards some other goal that has little to do with what the technology represents, rather than an invitation to revisit it, criticize its design, and try to make it better. This is an easy sell, because everyone likes something that makes their lives easier (or seems to), but we rob ourselves of something important in the process if that becomes the only end goal. What I see him proposing is that people with some skill should impose a high standard for design on themselves, drawing inspiration for that standard from how the best art humanity has produced was developed and nurtured, but guard against the sense of feeling small, inadequate, and overwhelmed by the challenge.

Maxwell (and Kay) explain further why this idea of “literacy” as being able to understand and communicate important ideas, which includes ideas about complexity, is something worth pursuing:

“If we look back over the last 400 years to ponder what ideas have caused the greatest changes in human society and have ushered in our modern era of democracy, science, technology and health care, it may come as a bit of a shock to realize that none of these is in story form! Newton’s treatise on the laws of motion, the force of gravity, and the behavior of the planets is set up as a sequence of arguments that imitate Euclid’s books on geometry.”

The most important ideas in modern Western culture in the past few hundred years, Kay claims, are the ones driven by argumentation, by chains of logical assertions that have not been and cannot be straightforwardly represented in narrative. …

But more recent still are forms of argumentation that defy linear representation at all: ‘complex’ systems, dynamic models, ecological relationships of interacting parts. These can be hinted at with logical or mathematical representations, but in order to flesh them out effectively, they need to be dynamically modeled. This kind of modeling is in many cases only possible once we have computational systems at our disposal, and in fact with the advent of computational media, complex systems modeling has been an area of growing research, precisely because it allows for the representation (and thus conception) of knowledge beyond what was previously possible. In her discussion of the “regime of computation” inherent in the work of thinkers like Stephen Wolfram, Edward Fredkin, and Harold Morowitz, N. Katherine Hayles explains:

“Whatever their limitations, these researchers fully understand that linear causal explanations are limited in scope and that multicausal complex systems require other modes of modeling and explanation. This seems to me a seminal insight that, despite three decades of work in chaos theory, complex systems, and simulation modeling, remains underappreciated and undertheorized in the physical sciences, and even more so in the social sciences and humanities.”

Kay’s lament too is that though these non-narrative forms of communication and understanding–both in the linear and complex varieties–are key to our modern world, a tiny fraction of people in Western society are actually fluent in them.

“In order to be completely enfranchised in the 21st century, it will be very important for children to become fluent in all three of the central forms of thinking that are now in use. […] the question is: How can we get children to explore ways of thinking beyond the one they’re ‘wired for’ (storytelling) and venture out into intellectual territory that needs to be discovered anew by every thinking person: logic and systems ‘eco-logic?'” …

In this we get Kay’s argument for ‘what computers are good for’ … It does not contradict Papert’s vision of children’s access to mathematical thinking; rather, it generalizes the principle, by applying Kay’s vision of the computer as medium, and even metamedium, capable of “simulating the details of any descriptive model.” The computer was already revolutionizing how science is done, but not general ways of thinking. Kay saw this as the promise of personal computing, with millions of users and millions of machines.

“The thing that jumped into my head was that simulation would be the basis for this new argument. […] If you’re going to talk about something really complex, a simulation is a more effective way of making your claim than, say, just a mathematical equation. If, for example, you’re talking about an epidemic, you can make claims in an essay, and you can put mathematical equations in there. Still, it is really difficult for your reader to understand what you’re actually talking about and to work out the ramifications. But it is very different if you can supply a model of your claim in the form of a working simulation, something that can be examined, and also can be changed.”

The computer is thus to be seen as a modeling tool. The models might be relatively mundane–our familiar word processors and painting programs define one end of the scale–or they might be considerably more complex. [my emphasis — Mark] It is important to keep in mind that this conception of computing is in the first instance personal–“personal dynamic media”–so that the ideal isn’t simulation and modeling on some institutional or centralized basis, but rather the kind of thing that individuals would engage in, in the same way in which individuals read and write for their own edification and practical reasons. This is what defines Kay’s vision of a literacy that encompasses logic and systems thinking as well as narrative.

And, as with Papert’s enactive mathematics, this vision seeks to make the understanding of complex systems something to which young children could realistically aspire, or that school curricula could incorporate. Note how different this is from having a ‘computer-science’ or an ‘information technology’ curriculum; what Kay is describing is more like a systems-science curriculum that happens to use computers as core tools:

“So, I think giving children a way of attacking complexity, even though for them complexity may be having a hundred simultaneously executing objects–which I think is enough complexity for anybody–gets them into that space in thinking about things that I think is more interesting than just simple input/output mechanisms.” (Maxwell, pp. 132-135)

I wanted to highlight the part about “word processors” and “paint programs,” because this idea that’s being discussed is not limited to simulating real world phenomena. It could be incorporated into simulating “artificial phenomena” as well. It’s a different way of looking at what you are doing and creating when you are programming. It takes it away from asking, “How do I get this thing to do what I want,” and redirects it to, “What entities do we want to make up this desired system, what are they like, and how can they interact to create something that we can recognize, or otherwise leverages human capabilities?”

Maxwell said that computer science is not the important thing. Rather, what’s important about computer science is what it makes possible: “the study and engagement with complex or dynamic systems–and it is this latter issue which is of key importance to education.” Think about this in relation to what we do with reading and writing. We don’t learn to read and write just to be able to write characters in some sequence, and then for others to read what we’ve written. We have events and ideas, perhaps more esoteric to this subject, emotions and poetry, that we write about. That’s why we learn to read and write. It’s the same thing with computer science. It’s pretty worthless, if we as a society value it for communicating ideas, if it’s just about learning to read and write code. To make the practice something that’s truly valuable to society, we need to have content, ideas, to read and write about in code. There’s a lot that can be explored with that idea in mind.

Characterizing Alan Kay’s vision for personal computing, Maxwell talked about Kay’s concept of the Dynabook:

Alan Kay’s key insight in the late 1960s was that computing would become the practice of millions of people, and that they would engage with computing to perform myriad tasks; the role of software would be to provide a flexible medium with which people could approach those myriad tasks. … [The] Dynabook’s user is an engaged participant rather than a passive, spectatorial consumer—the Dynabook’s user was supposed to be the creator of her own tools, a smarter, more capable user than the market discourse of the personal computing industry seems capable of inscribing—or at least has so far, ever since the construction of the “end-user” as documented by Bardini & Horvath. (p. 218)

Kay’s contribution begins with the observation that digital computers provide the means for yet another, newer mode of expression: the simulation and modeling of complex systems. What discursive possibilities does this new modality open up, and for whom? Kay argues that this latter communications revolution should in the first place be in the hands of children. What we are left with is a sketch of a possible new literacy; not “computer literacy” as an alternative to book literacy, but systems literacy—the realm of powerful ideas in a world in which complex systems modelling is possible and indeed commonplace, even among children. Kay’s fundamental and sustained admonition is that this literacy is the task and responsibility of education in the 21st century. The Dynabook vision presents a particular conception of what such a literacy would look like—in a liberal, individualist, decentralized, and democratic key. (p. 262)

I would encourage interested readers to read Maxwell’s paper in full. He gives a rich description of the problem of computers in the educational context, giving a much more detailed history of it than I have here, and what the best minds on the subject have tried to do to improve the situation.

The main point I want to get across is if we as a society really want to get the greatest impact out of what computers can do for us, beyond just being tools that do canned, but useful things, I implore educators to see computers and programming environments more as apparatus, instruments, media (the computers and programming environments themselves, not what’s “played” on computers, and languages and metaphors, which are the media’s means of expression, not just a means to some non-expressive end), rather than as agents and tools. Sure, there will be room for them to function as agents and tools, but the main focus that I see as important in this subject area is in how the machine helps facilitate substantial pedagogies and illuminates epistemological concepts that would otherwise be difficult or impossible to communicate.

—Mark Miller, https://tekkie.wordpress.com

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This exercise in Section 3.3.3 demonstrates a concept called “memoization,” where values that are created during the run of a function are stored, so that when requests for certain computations repeat, the previously computed values can just be retrieved, rather than redone. It’s a caching technique.

I got really frustrated trying to do this exercise, because of the way the make-table function was portrayed. The exercise text doesn’t say anything about it. The code that was given for the exercise just uses it. In the past, exercises would use code that had already been introduced and discussed in the section/chapter. There is a set of functions that implement a single-dimension table (all that would be needed for this exercise) that is discussed earlier in the section. When I brought what I thought were the appropriate functions together, what I saw was this:

(define (make-table)
   (list '*table*))

(define memo-fib
   (memoize (lambda (n)
               (cond ((= n 0) 0)
                     ((= n 1) 1)
                     (else (+ (memo-fib (- n 1))
                              (memo-fib (- n 2))))))))

(define (memoize f)
   (let ((table (make-table)))
      (lambda (x) ...

Even the two-dimensional versions of make-table that were presented initialized their local table the same way. I’m used to paying attention to details in code, and so I tried to make sense of this. Every time memo-fib got called, the table got reinitialized, wiping out everything that had been added to it! This made no sense for this exercise, since the whole idea was to store values in the table, and then retrieve them later.

By looking at what other people had done with this exercise, I realized that I needed to use “wishful thinking,” and ignore any prior implementations of make-table. Just assume that make-table initializes its table structure on the first call, and returns a reference to its table (or a reference to a dispatch function) on subsequent calls to it. Assume that it does not reinitialize its internal structure, leaving anything that was previously added intact. Once I made these assumptions, the exercise made more sense.

What I saw other people do as well was assume that the insert! and lookup functions operated in constant time, taking them out as a factor in the number of steps. I do not know what assumptions are “supposed” to be made about the insert! and lookup functions. If you are doing this exercise for a grade, take these assumptions at your own risk. To me, it made sense, but perhaps your professor has a different idea in mind for how these functions are supposed to be considered in your analysis.

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** Warning: This article contains spoiler information. Do not read further if you don’t want the story revealed. I wrote this article for people who have seen the movie. **

I was disappointed in Tron Legacy at first. I didn’t get the same thrill out of it that I got out of Tron when I first saw it at age 14. In some ways it met my expectations. Based on the previews, I figured it would suggest that technologists have gotten obsessive about technology, and they need to “get out more.” It did that, but at first blush it appeared to do nothing more. I thought about what I had watched, and some things came more into focus that made me like it a lot more.

I’ve read a couple movie reviews on it, and I feel as though they missed the point, but that should not be surprising. Like with the original Tron, this movie works on a few levels. If you are a typical moviegoer, the movie’s story line will entertain you, and the special effects will dazzle you. A couple reviews have said that it follows the story line of a particular kind of a fairy tale. I think it does, but this is just superficial.

With Tron in 1982, the “surface” story was a bit like the movie The Incredible Shrinking Man in that a character is transported into a micro-reality, and everything that once appeared small and insignificant became huge and menacing. The main character, Kevin Flynn, had to face the games he created, inside the system created by his former employer. A virtual, mysterious and reclusive master overlord (the MCP) sought to grab up other entities (called “programs”) and systems to merge with itself, so it could become more powerful. A recurring theme was a kind of atheism. Programs were expected to believe that only their own reality existed, that there were no such things as “users,” (something greater than themselves, off in another reality they could not relate to, but which had a direct relationship with them). This was so that the programs would feel helpless, and would not fight the overlord. Flynn, a user, is sucked in because the system is so arrogant it thinks it can defeat him as well.

The message embedded in the film, which technologists would understand, was political: Were we going to have centralized control of computing, which had implications for our rights, or was computer access going to be democratized (a “free system”), so that people could have transparent access to their alter-egos inside the computer world? This was a futuristic concept in one sense, because most people were not aware of this relationship, even though it was very real at the time (but not in the sense of “little computer people”). I thought of it as expressing as well that the computer world reflected the consciousness of whichever user had the most influence over it (ie. Dillinger).

The director of “Tron,” Steven Lisberger, talked about how we had alter-egos in the computer world in the form of our tax records, and our financial transactions, and that in the future this alter-ego was only going to grow in its sophistication as more data was gathered about us. The future that was chosen largely agrees with the preferred outcome in the movie. Though we have this alter-ego that exists in the computer world, computer access was democratized, just not quite in the way the movie predicted.

There was a metaphysical message that’s more universal: Just as computer programs have users, perhaps we have “users” as well in some reality to which we can’t relate. The creators of the movie deliberately tried to make the real world look a little like the computer world to make this point. The theme that Lisberger has talked about many times now is that perhaps we all have a “better self,” and the question is are we going to strive to access that better self, or are we going to go through life never trying to get in touch with it?

What drew me into “Tron” when I first saw it in about 1983 was the idea that in the computer world things could be shaped by our thoughts and consciousness. I had a feel for that, since I had started programming computers 2 years earlier. Dr. Walter Gibbs’s confrontation with Dillinger particularly resonated with me:

You can remove men like Alan and me from the system, but we helped create it! And our spirit remains in every program we design for this computer!

Tron Legacy is a decidedly different movie from the old Tron. It has some elements that are reminiscent of it, but the message is different. I won’t talk too much about the fairy tale aspect, but instead focus on the message that I think is meant for technologists. This will be my own interpretation of it. This is what it inspired for me.

Instead of talking about a complaint about current conditions, as if they had no antecedent, the movie subtly complains about a problem that’s existed from the time when “Tron” was made, in our world: The legacy of the technical mentality that came into dominance at the same time that the democratization of computer access occurred, and has existed ever since.

On the surface, in the real world (in the movie), the computer industry is slouching towards cynical commercialism. Kevin Flynn disappeared 21 years earlier, leaving behind his son, Sam. Encom lost its visionary, and innovation at the company gradually slowed. In the present, the idea of technological innovation is dead. Encom is set to release yet another version of its operating system (Version 12), which they claim is the most secure they’ve ever released. Alan Bradley, a member of the board, asks something to the effect of, “What’s really new about this product?” He’s told, “We put the number 12 on it.” They decide to sell the OS commercially (as I recall, it was given away freely in prior versions, according to the history told in the movie). Alan is part of the company, but he doesn’t have much power. Instead of talking about what their R&D has produced (if any R&D existed), one of the executives touts the fact that Encom stock will soon be traded 24 hours a day, all around the world. The company has lost its soul, and is now only concerned with coasting, milking its past innovation for all it’s worth.

Sam exists outside Encom for the most part, but is the company’s largest stockholder. In a nod to the free software crowd, when he hears about the Encom announcement, he decides to break into the company (like his father did many years earlier), hack into its data center and make the operating system freely available on the internet (odd…I thought the operating system was the most secure ever…), dashing the company’s plans to sell it. Shortly thereafter, Alan shows up at Sam’s garage apartment, telling him he received a page from an old number his father used at the “Flynn’s” arcade. Sam is alienated and uninterested, saying his father is dead. He seems lost, and without purpose. His only involvement in the story is to create mischief. Going deeper into this, we can see in mischief a desire to be involved, to change things, and yet not take responsibility for it, to not really try to do better. Maybe the reason is there’s a sense of incompatibility with one’s surroundings, but the mischief makers can’t quite put their finger on what the problem is. So their only answer is to attack what is.

For years Alan said that Flynn was still alive. He persists with Sam, saying there must be a good reason his father disappeared, that it wasn’t because he had intentionally abandoned him. He throws Sam the keys to the old arcade, and thus the voyage “down the rabbit hole” begins…

Inside the computer world, Sam goes through a similar initiation that his father went through in “Tron,” and then he is entered into gladiatorial games–most of the same games that his father competed in, only more advanced and modernized. Sam competes well, and survives. After a similar escape from “the game grid” as his father pulled off in the original movie (except with the help of a computer character named Quorra), Sam meets his father, Kevin Flynn, in an isolated cave (though with very nice accommodations). The look of this “cave” is reminiscent of the end scene in 2001: A Space Odyssey. I won’t go into the details of what Sam and Kevin talk about. What I found interesting was that Kevin had spent a significant amount of time studying philosophy. Based on this background, he plays the role of a wise, though defeated, sage.

Kevin tells the story of how he became trapped in a world of his own creation (rather like in “Tron,” but this time Kevin never found a way out). A theme that emerges is the danger of perfectionism, a seductive quality of computer systems. This is embodied in a program Kevin created, named Clu. In the beginning of the computer world, Clu was helpful. As the system was being built from the inside, some mysterious entities “emerged” in the system. Kevin called them “isomorphs.” He marveled at them, and hoped they would become a part of the system. Their programming had such complexity and sophistication he had trouble understanding their makeup.

I recognize the idea of “emergence” from my days studying CS in college. There were many people back then who had this romantic idea that as the internet grew larger and larger, an “intelligence” would eventually “emerge” out of the complexity.

Later in the history told in the movie, Clu turned dogmatic about perfection. He killed off the isomorphs, and threatened Kevin. Kevin tried fighting Clu, but the more he did so, the stronger Clu got. So he hid in his cave, all this time. Meanwhile Clu built the game grid into his vision of “the perfect system.” Everything is “perfect” in his world. One would think this is ideal, but there is a flip side. Imperfections are rejected. Eventually Kevin came to understand that his desire to create “the perfect system” led to one that’s hostile, not utopian as he had imagined. He realizes he made a mistake. There is an interesting parallel between this story line and what happened with Encom, and indeed what happened with the computer industry in our world. By being trapped in his own system, being exposed to the isomorphs, and seeing how his vision was incompatible with this wonderful and mysterious new entity, and himself, Kevin is forced to come face to face with himself, and the vision he had for the computer world. He is given the opportunity to reconsider everything.

There were some subtle messages conveyed. I noticed that anytime one of the programs in the gladiatorial games, or one of Clu’s henchmen got hit with a weapon, or hit a barrier, they died instantly–derezzing. However, with Quorra, Kevin’s companion in the cave, when she gets hurt in a fight, the damaged part of her derezzes, but she remains alive. What this communicated to me is that Kevin and Clu imposed designs on the system whose only purpose was to serve a single goal. They imposed an image of perfection on everything they created, which meant that any imperfection that was introduced into one of these programs (a “wound”) caused it to fall apart and die. Is this not like our software?

Quorra was not created by Flynn, and her system did not demand perfection. She was fault-tolerant. If a piece of her system was damaged, the rest of her was affected (she goes into a “dormant” state), but she did not die. Sam realizes after she is damaged that Quorra is an isomorph. The last of her kind.

I realized, reading an article just recently on Category Theory, and it’s application to programmable systems, called, “Programmers go bananas,” by José Ortega-Ruiz, that “isomorph” is a term used in mathematics. Just translating the term, it means “equal form,” but if you read the article, you’ll get somewhat of a sense of what Quorra and the isomorphs represented:

A category captures a mathematical world of objects and their relationships. The canonical example of a category is Set, which contains, as objects, (finite) sets and, as arrows, (total) functions between them. But categories go far beyond modeling sets. For instance, one can define a category whose objects are natural numbers, and the ‘arrows’ are provided by the relation “less or equal” (that is, we say that there is an arrow joining two numbers a and b if a is less or equal than b). What we are trying to do with such a definition is to somehow capture the essence of ordered sets: not only integers are ordered but also dates, lemmings on a row, a rock’s trajectory or the types of the Smalltalk class hierarchy. In order to abstract what all those categories have in common we need a way to go from one category to another preserving the shared structure in the process. We need what the mathematicians call an isomorphism, which is the technically precise manner of stating that two systems are, in a deep sense, analogous [my emphasis]; this searching for commonality amounts to looking for concepts or abstractions, which is what mathematics and (good) programming is all about (and, arguably, intelligence itself, if you are to believe, for instance, Douglas Hofstadter‘s ideas).

Ruiz went on to talk about relationships between objects and categories being isomorphic if one object, or a set of objects in a category O could be transformed into another object/category O’, and back to O again. In other words, there was a way to make two different entities “equal” or equivalent with each other via. transforming functions (or functors). I think perhaps this is what they were getting at in the movie. Maybe an isomorph was equivalent to a biological entity, perhaps even a human, in the computer world, but in computational terms, not biological.

I offer a few quotes from my post, “Redefining computing, Part 2,” to help fill in the picture some more Re. the biological/computational analogy. In this post, I used Alan Kay’s keynote address at OOPSLA ’97, called “The Computer Revolution Hasn’t Happened Yet.” The goal of his presentation was to talk about software and network architecture, and he used a biological example as a point of inspiration, specifically an E. Coli bacterium. He starts by talking about the small parts of the bacterium:

Those “popcorn” things are protein molecules that have about 5,000 atoms in them, and as you can see on the slide, when you get rid of the small molecules like water, and calcium ions, and potassium ions, and so forth, which constitute about 70% of the mass of this thing, the 30% that remains has about 120 million components that interact with each other in an informational way, and each one of these components carries quite a bit of information [my emphasis]. The simple-minded way of thinking of these things is it works kind of like OPS5 [OPS5 is an AI language that uses a set of condition-action rules to represent knowledge. It was developed in the late 1970s]. There’s a pattern matcher, and then there are things that happen if patterns are matched successfully. So the state that’s involved in that is about 100 Gigs. … but it’s still pretty impressive as [an] amount of computation, and maybe the most interesting thing about this structure is that the rapidity of computation seriously rivals that of computers today, particularly when you’re considering it’s done in parallel. For example, one of those popcorn-sized things moves its own length in just 2 nanoseconds. So one way of visualizing that is if an atom was the size of a tennis ball, then one of these protein molecules would be about the size of a Volkswagon, and it’s moving its own length in 2 nanoseconds. That’s about 8 feet on our scale of things. And can anybody do the arithmetic to tell me what fraction of the speed of light moving 8 feet in 2 nanoseconds is?…[there’s a response from the audience] Four times! Yeah. Four times the speed of light [he moves his arm up]–scale. So if you ever wondered why chemistry works, this is why. The thermal agitation down there is so unbelievably violent, that we could not imagine it, even with the aid of computers. There’s nothing to be seen inside one of these things until you kill it, because it is just a complete blur of activity, and under good conditions it only takes about 15 to 18 minutes for one of these to completely duplicate itself. …

Another fact to relate this to us, is that these bacteria are about 1/500th the size of the cells in our bodies, which instead of 120 million informational components, have about 60 billion, and we have between 1012, maybe 1013, maybe even more of these cells in our body.

So to a person whose “blue” context might have been biology, something like a computer could not possibly be regarded as particularly complex, or large, or fast. Slow. Small. Stupid. That’s what computers are. So the question is how can we get them to realize their destiny?

So the shift in point of view here is from–There’s this problem, if you take things like doghouses, they don’t scale [in size] by a factor of 100 very well. If you take things like clocks, they don’t scale by a factor of 100 very well. Take things like cells, they not only scale by factors of 100, but by factors of a trillion. And the question is how do they do it, and how might we adapt this idea for building complex systems?

So a lot of the problem here is both deciding that the biological metaphor [my emphasis] is the one that is going to win out over the next 25 years or so, and then committing to it enough to get it so it can be practical at all of the levels of scale that we actually need. Then we have one trick we can do that biology doesn’t know how to do, which is we can take the DNA out of the cells, and that allows us to deal with cystic fibrosis much more easily than the way it’s done today. And systems do have cystic fibrosis, and some of you may know that cystic fibrosis today for some people is treated by infecting them with a virus, a modified cold virus, giving them a lung infection, but the defective gene for cystic fibrosis is in this cold virus, and the cold virus is too weak to actually destroy the lungs like pneumonia does, but it is strong enough to insert a copy of that gene in every cell in the lungs. And that is what does the trick. That’s a very complicated way of reprogramming an organism’s DNA once it has gotten started.

Recall that when Kevin works on Quorra’s damaged body, he brings up a model of her internal programming, which looks like DNA. Recall as well that when Alan Bradley talked to Sam about the page he got, he told Sam about a conversation he had with Kevin Flynn before he disappeared. Kevin said that he had found something that was revolutionary, that would change science, religion, medicine, etc. I can surmise that Kevin was talking about the isomorphs. When I thought back on that, I thought about what I quoted above.

Moving on with Alan Kay’s presentation, here’s a quote that gets close to what I think is the heart of the matter for “Tron Legacy.” Kay brings up a slide that on one side has a picture of a crane, and on the other has a picture of a collection of cells. More metaphors:

And here’s one that we haven’t really faced up to much yet, that now we’ll have to construct this stuff, and soon we’ll be required to grow it. [my emphasis] So it’s very easy, for instance, to grow a baby 6 inches. They do it about 10 times in their life. You never have to take it down for maintenance. But if you try and grow a 747, you’re faced with an unbelievable problem, because it’s in this simple-minded mechanical world in which the only object has been to make the artifact in the first place, not to fix it, not to change it, not to let it live for 100 years.

So let me ask a question. I won’t take names, but how many people here still use a language that essentially forces you–the development system forces you to develop outside of the language [perhaps he means “outside the VM environment”?], compile and reload, and go, even if it’s fast, like Virtual Cafe (sic). How many here still do that? Let’s just see. Come on. Admit it. We can have a Texas tent meeting later. Yeah, so if you think about that, that cannot possibly be other than a dead end for building complex systems, where much of the building of complex systems is in part going to go to trying to understand what the possibilities for interoperability is with things that already exist.

Now, I just played a very minor part in the design of the ARPANet. I was one of 30 graduate students who went to systems design meetings to try and formulate design principles for the ARPANet, also about 30 years ago, and if you think about–the ARPANet of course became the internet–and from the time it started running, which is around 1969 or so, to this day, it has expanded by a factor of about 100 million. So that’s pretty good. Eight orders of magnitude. And as far as anybody can tell–I talked to Larry Roberts about this the other day–there’s not one physical atom in the internet today that was in the original ARPANet, and there is not one line of code in the internet today that was in the original ARPANet. Of course if we’d had IBM mainframes in the orignal ARPANet that wouldn’t have been true. So this is a system that has expanded by 100 million, and has changed every atom and every bit, and has never had to stop! That is the metaphor we absolutely must apply to what we think are smaller things. When we think programming is small, that’s why your programs are so big!

Another thing I thought of, relating to the scene where Quorra is damaged, and then repaired, is the way the Squeak system operates, just as an example. It’s a fault-tolerant system that, when a thread encounters a fault, pauses the program, but the program doesn’t die. You can operate on it while it’s still “alive.” The same goes for the kernel of the system if you encounter a “kernel panic.” The whole system pauses, and it’s possible to cancel the operation that caused the panic, and continue to use the system. As I thought back on the movie, I could not help but see the parallels to my own experience learning about this “new” way of doing things.

The problem with creating a “perfect system” is it requires the imposition of rules that demand perfection. This makes everything brittle. The slightest disturbance violates the perfection and causes the whole thing to fall apart. Also, perfection is limiting, because it must have a criteria, and that criteria must necessarily be limited, because we do not know everything, and never will. Not that striving for perfection is itself bad. Having a high bar, even if it’s unachievable, can cause us to strive to be the best that we can be. However, if we’re creating systems for people to use, demanding perfection in the system in effect demands perfection from the people who design and use it. This causes systems that are vulnerable and brittle. This makes people feel scared to use them, because if they do something wrong, it’ll go to pieces on them, or misinterpret their actions, and do something they don’t want. It also allows hackers to exploit the human weaknesses of the software’s designers to cause havoc in their systems and/or steal information.

Just thinking this out into the story of “Tron Legacy,” Quorra’s characteristics were probably the reason Clu tried to kill off the isomorphs. He didn’t understand their makeup, or their motivation. Their very being did not have the same purpose as he had for the overall system. They were not designed to contribute to a singular goal. Instead, their makeup promoted self-sustaining, self-motivated entities. Their allowance for imperfection, their refusal to adhere to a singular goal, in his mind, was dangerous to the overall system goal.

The “end game” in the story goes as such. Sam’s entry into the system opened a portal inside the computer system back to the real world. This presents an opportunity for Clu. He has been secretly generating an army that he hopes to use to take over the real world, and he plans to use the opportunity of the open portal. This particular sequence brought to mind the formation of the Grand Army of the Republic in the 2nd movie in the most recent Star Wars trilogy, Attack of the Clones. It also had a “sorcerer’s apprentice” (from Fantasia) quality about it, in that Kevin created something, but despite his intentions, his creation got out of his control, and became dangerous.

To me, the main computer characters in the movie were metaphors for different philosophies of what computer systems are supposed to be. Clu and his army are symbolic of the dominant technical mentality in computing today that imposes perfection on itself, and humanity, a demand that can never completely be satisfied. Quorra represents a different idea, and I’ve occasionally puzzled over it. Were the origins of the isomorphs meant to convey an evolutionary process for computer systems whereby they can evolve on their own, or was that just a romantic idea to give the story a sense of mystery? The best way I can relate to what Quorra is “made of” is that she and the isomorphs are a computational “organism” that is made up of elements in a sophisticated architecture that is analogous to human anatomy, in terms of the scale her software is able to achieve, the complexity it is able to encompass, the intelligence she has, her curiosity, and her affinity for humanity. She represents the ideal in the story, in contrast to Flynn’s notions of perfection.

I think the basic idea of the movie is that in the early going, people like Flynn were smart, witty, and clever. They were fascinated by what they could create in the computer world, and they could create a lot, but it was divorced from humanity, and they became fascinated by the effort of trying to make that creation better. What they missed is that the ideal creation in the computer world is more like us, both in terms of its structure and intelligence.

The final scene in the movie was a bit of a surprise. At first blush it was the most disappointing part of it for me, because I wondered, “How did they make *that* work??” I was tempted to extend the “isomorph” idea still further as I wrote this post, to say that a computer entity could be transformed into a human, just as the term “isomorphic” suggests, but I don’t know if that’s what the creators of the movie were going for. After all, Clu thought he could bring an entire army of computer entities into the real world, including himself. How was that going to work? I think that interpretation was too literal. Going along with the idea that Quorra is a symbolic character, what I took away from it was that Sam was taking this new idea out of Flynn’s “enclave,” and bringing it into the world. He said to Alan Bradley after they got out that he was going to take the helm at Encom. Sam had found a purpose in his life. It was a message of hope. It was a way for him to honor his father, to learn from his mistakes, and try to do better. There’s also a hopeful message that computers will join us in our world, and not require us to spend a lot of time in the world we’ve created inside the computer.

“Tron Legacy” asks technologists to reassess what’s been created at a much deeper technical level than I expected. It does not use technical jargon much, but subtly suggests some very sophisticated ideas. The philosophical issues it presents have deep implications for technology that are much more involved than how our computer access is organized (a technical theme of the first movie). It prompts us to ask uncomfortable, fundamental questions about “what we have wrought” in our information age, not in the sense of the content we have produced, but about how we have designed the systems we have given to the world. It also prompts us to ask uncomfortable questions about, “What do we need to do to advance this?” How do we get to a point where we can create the next leap that will bring us closer to this ideal? I think it dealt with issues which I have talked about on this blog, but extends far beyond them.

It will be interesting to see the DVD when it comes out. I wonder what the creators of the movie will say about their inspirations for what they put into it. I have not played the video game Tron Evolution, which I’ve heard tells the story from the time of the first movie up to “Tron Legacy.” Maybe it tells a very different story.

I leave you with a PC graphics/sound demo called “Memories from the MCP,” created in 2005 by a group called “Brain Control”. It looks pretty cool, and is vaguely Tron-ish. It has a “Tron Legacy” look and sound to it.

Edit 12-14-2012: I noticed there was some traffic coming to this post from Reddit. I looked at the discussion going on there, and someone referred to this video, created by Bob Plissken, called “Tron: Fight For The Users.” It kind of dovetails with what I talk about here, but it offers a different perspective. I like that it shows how both “Tron” and “Tron Legacy” try to get across similar messages. I don’t entirely agree with the idea that “we are the users of ourselves.” I’d say we are currently the users of notions of system organization, given to us by designers. These notions have had implications, which we have seen play out over the last 20 years in particular. Still, I like this message for its depth of perception. This sort of deep look at the symbolic implications of the stories, as they relate to the technological society we live in, is the way I like to look at the Tron movies.

At the end it refers people to a blog called Yori Lives. I checked it out, and a post called “Tron and the Future” nicely explains the message in this video.

On another subject, there’s been a lot of buzz lately about a sequel to “Tron Legacy” (for lack of a better term, it seems people are calling it “Tron 3”). Apparently there is some reason to be excited about it, as there’s been news that Disney is actively pursuing this. Yori Lives also talks about it.

— Mark Miller, https://tekkie.wordpress.com

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I’m backtracking with this post. My last SICP post talked about sections 2.2 and 2.3. I’m now going back to Section 1.2 to cover an exercise I had not done until recently. I may get into more of them. Time will tell.

One of the things Section 1.2 talks about is how to calculate Fibonacci numbers recursively and iteratively. The recursive procedure is O(Φn), and the iterative method is O(n). Another concept this section brings up over and over again is exponentiation, and this exercise prompts you to look at it in a new way: It just means repeating something n times, and the operation doesn’t necessarily have to do with multiplication.

The exercise says there’s an algorithm for calculating Fibonacci numbers in O(log n). I had a few false starts with this. The only way I was able to figure it out was to go through the text of the exercise slowly and methodically, and do what each part prompted me to do, before going on to the next sentence. I think once again my ignorance of mathematics came out, because it looks like this exercise was written by a mathematician. The author had a way of expressing things that was foreign to me, and so I had to spend some time teasing out what they meant. I’m going to break up the exercise text into “bite size” pieces to clarify what’s being communicated.

The first part I worked on was:

Recall the transformation of the state variables a and b in the fib-iter process of section 1.2.2: aa + b and ba. Call this transformation T, and observe that applying T over and over again n times, starting with 1 and 0, produces the pair Fib(n + 1) and Fib(n).

I’m not going to give you the play-by-play of this step, but I will clarify what the author is saying. Where it says, “Call this transformation T“, it means keep this association in mind:

T: aa + b and ba (In other words, when you think of T, think of the transformation aa + b and ba)

By “transformation” they mean, for example, “The new value of a (to the left of the arrow) is derived from the formula on the right side of the arrow.” The same goes for b. Where it says, “observe that applying T over and over again n times, starting with 1 and 0, produces the pair Fib(n + 1) and Fib(n),” it means calculate the values for a and b by using the transformation T and apply the results to itself over and over again, starting with the values a = 1, and b = 0. Observe that the pattern of pairs (the values for a and b) is the same as if you had calculated the Fibonacci pairs Fib(n + 1) and Fib(n) for each transformation step.

Think of this as “Step 1” for the exercise. It’s important that you do it, because this sequence of calculations becomes relevant later.

Next, it gets into an expanded concept of exponentiation:

In other words, the Fibonacci numbers are produced by applying Tn, the nth power of the transformation T, starting with the pair (1,0).

All the author is trying to do here is recast what you just did (applying the transformation T to itself over and over again) as the concept of taking something to the nth power. It does not change the meaning of what you did at all. All it represents is looking at what you did in a different way; in a way you probably had never imagined was possible. The reason the author wrote this was to help you relate to a concept, which will be introduced later in the exercise text.

Just a little hint here. Since the exercise brought up the issue of exponents in relation to iterations of the transformation T, I noticed that it was helpful later on if I put the corresponding exponent (1, 2, 3, etc.) next to each Fibonacci pair in the part I labeled above, “Step 1”.

Next, it gets really confusing! I don’t know about you, but I think they could’ve written this more clearly. Ready? Here we go!

Now consider T to be the special case of p = 0 and q = 1 in a family of transformations Tpq, where Tpq transforms the pair (a,b) according to abq + aq + ap and bbp + aq.

I had to look at this sentence a bunch of times before I got it. What I got hung up on was the use of the term “T” and the reuse of the variables a and b in the transformation, combined with the fact that the only variables that appeared to be associated with T (on first blush) were p and q. I had to keep in mind, though, that a and b were not used as annotations for the transformation T above, either. I think the reason for the “pq” annotation will become clear as you go through this part.

What the author is really saying is, “Let’s bring in a different kind of transformation we’ll call Tpq. It’s defined as: Tpq: abq + aq + ap and bbp + aq.” The transformation T has not changed. It still exists (separate from Tpq), and it’s still: T: aa + b and ba. What the author is saying is, “If you use (apply) transformation Tpq with the parameters p = 0 and q = 1, the algebraic result is the same as the transformation T.” Go ahead. Give it a try, and convince yourself this statement is true.

This is a setup for the next sentence, which is equally as confusing as the last one:

Show that if we apply such a transformation Tpq twice, the effect is the same as using a single transformation Tp’q’ of the same form, and compute p’ and q’ in terms of p and q.

Okaaaaay. Got it? The way I interpreted this was, “Apply Tpq twice, with the parameters p = 0 and q = 1. Next, let’s introduce a second instance of the formula for Tpq we’ll call “Tp’q’“, with variables p’ and q’ (abq’ + aq’ + ap’ and bbp’ + aq’ — This is where “of the same form” comes from). See if you can find a way to make Tp’q’ equal the second-order transformation of Tpq (the one where you applied the transformation twice with the parameters p = 0 and q = 1). Once you’ve done this, come up with a way to derive the values for p’ and q’ from p and q.” Anyway, this interpretation worked for me. I hope I’ve expressed this clearly. I’m leaving a bit of mystery here to maintain fidelity to the way the original exercise was written.

I’m going to leave this part as a challenge for you to figure out, though the last part of the exercise text (below) gives you a clue about what’s going on here. I’ll just say that everything you have done from the beginning of this exercise up to this point has provided you with all of the information you need to come up with the solution for this.

The exercise finishes with:

This gives us an explicit way to square these transformations, and thus we can compute Tn using successive squaring, as in the fast-expt procedure. Put this all together to complete the following procedure, which runs in a logarithmic number of steps.

A Scheme procedure follows in the text, where most of the code is filled in. All you have to do is fill in the steps where p’ and q’ need to be computed. (Note: I talked about fast-expt earlier here).

Okay, now I think this ending is somewhat misleading. I did not find after doing the above steps that I immediately knew how to do successive squaring in this exercise. It’s going to take some thinking on your part, considering what you’ve done up to this point, to figure out how to do this. What the Scheme code makes obvious is the act of successive squaring takes place solely in the code that computes p’ and q’. I will say that the behavior of successive squaring here is like that of successive squaring in the exercise with fast-expt (Exercise 1.16) in the sense that you’re “jumping” to successive values to get to Fib(n), rather than computing each value as you incrementally approach n.

One hint I’ll give you is once you think you’ve figured out how to compute p’ and q’ in the code, make sure you try out higher values of n with the “fib” procedure in this exercise, like Fib(10), Fib(11), Fib(12), etc., and compare what you get with the known Fibonacci sequence (you can compare it with output of some other version of the “fib” procedure that’s discussed earlier in this section, or you can look up the sequence on the internet). You’ll probably realize that the formulas you came up with are wrong when you do this (I did), and you need to re-evaluate them. The exercise guides you a part of the way to the answer, but makes it sound like you’ve made it most of the way, when you really haven’t.

Maybe I just need to hang out with mathematicians more to see how they use language, but I thought this exercise was poorly written. It seemed to try to hide things by being obscure, to make the problem more challenging, rather than being straightforward and setting forth the challenge in the last step, which is really where it is.

This exercise is worth doing for the beautiful solution that results. It goes to show that no matter how efficient you think your algorithm is, it’s worth exploring to see if you can make it even more efficient, and that mathematics is key to figuring out how to do that.

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