Wednesday, February 16, 2005

A Conversation with Alan Kay

A Conversation with Alan Kay:

A wonderful interview; I really admire Kay's attitude, not to mention his brilliance.

SF So Smalltalk is to Shakespeare as Excel is to car crashes in the TV culture?

AK No, if you look at it really historically, Smalltalk counts as a minor Greek play that was miles ahead of what most other cultures were doing, but nowhere near what Shakespeare was able to do.

If you look at software today, through the lens of the history of engineering, it’s certainly engineering of a sort—but it’s the kind of engineering that people without the concept of the arch did. Most software today is very much like an Egyptian pyramid with millions of bricks piled on top of each other, with no structural integrity, but just done by brute force and thousands of slaves.


I don’t spend time complaining about this stuff, because what happened in the last 20 years is quite normal, even though it was unfortunate. Once you have something that grows faster than education grows, you’re always going to get a pop culture. It’s well known that I tried to kill Smalltalk in the later ’70s...


SF If nothing else, Lisp was carefully defined in terms of Lisp.

AK Yes, that was the big revelation to me when I was in graduate school—when I finally understood that the half page of code on the bottom of page 13 of the Lisp 1.5 manual was Lisp in itself. These were “Maxwell’s Equations of Software!” This is the whole world of programming in a few lines that I can put my hand over.

I realized that anytime I want to know what I’m doing, I can just write down the kernel of this thing in a half page and it’s not going to lose any power. In fact, it’s going to gain power by being able to reenter itself much more readily than most systems done the other way can possibly do.

All of these ideas could be part of both software engineering and computer science, but I fear—as far as I can tell—that most undergraduate degrees in computer science these days are basically Java vocational training.

I’ve heard complaints from even mighty Stanford University with its illustrious faculty that basically the undergraduate computer science program is little more than Java certification.


This project that we started in 1995 was to make Squeak as an implementation vehicle for another end-user system for children. That was done quite well and is being used by many, many thousands of children around the world. The other way of looking at this is to realize that computers are made to be programmed by human beings. Let’s just roll our own. Let’s not complain about Java, or even about Smalltalk.

In fact, let’s not even worry about Java. Let’s not complain about Microsoft. Let’s not worry about them because we know how to program computers, too, and in fact we know how to do it in a meta-way. We can set up an alternative point of view, and we’re not the only ones who do this, as you’re well aware.


our basic language mechanism for both reading and hearing has a fast and a slow process. The fast process has basically a surface phrasal-size nature, and then there’s a slower one. This is why jokes require pauses; the joke is actually a jump from one context to another, and the slower guy, who is dealing with the real meanings, has to catch up to it.

There have been many, many studies of this. This argues that the surface form of a language, whatever it is, has to be adjustable in some form.SF As you probably know, recent research has looked at how different parts of the brain recognize and react to jokes. Physically, they are quite distinct.

AK Yes. All creativity is an extended form of a joke. Most creativity is a transition from one context into another where things are more surprising. There’s an element of surprise, and especially in science, there is often laughter that goes along with the “Aha.”


SF What do you wish you had done differently in the Smalltalk era?

AK I had the world’s greatest group, and I should have made the world’s two greatest groups. I didn’t realize there are benefits to having real implementers and real users, and there are benefits to starting from scratch every few months. I hired finishers because I’m a good starter and a poor finisher, but it took me a long time to realize that I was interfering with them by trying to improve things.

I believe that the only kind of science computing can be is like the science of bridge building. Somebody has to build the bridges and other people have to tear them down and make better theories, and you have to keep on building bridges.