The most named person in the book: Donald Knuth. The author of “The Art of computer programming” Many people, including me, have not read it. But it justifies us.

Seibel: Uh-oh; you just revealed your secret there.

Knuth: Yeah, right. Then I decided I would write a little program to calculate the prime factors of a number. It was about 100 lines long. I would come at night when nobody else was using the machine, and debug it. And I found more than 100 bugs in my 100-line program. But 2 weeks later I had a
program that would find prime factors of any 10-digit number that you dialed into the console switches.

That was how I learned programming—basically taking one program that I made up myself and sitting at a machine over a period of some weeks, and kept getting it to work a little better and a little better.

My second program was converting between binary and decimal. But my third program was a program to play tic-tac-toe and that was what really made me a programmer.

I had to use data structures for that. I made three versions of tic-tac-toe, one of which was self-learning so that it would start out knowing nothing about the game and then it would remember every time it lost a game that the moves it made were suspicious and the moves that the opponent made were good, and it would upgrade the quality of certain positions and downgrade the quality of other positions, and then after you played 400 games it would do a fairly decent job of tic-tac-toe.

Seibel: It seems a lot of the people I’ve talked to had direct access to a machine when they were starting out. Yet Dijkstra has a paper I’m sure you’re familiar with, where he basically says we shouldn’t let computer science students touch a machine for the first few years of their training; they should spend all their time manipulating symbols.

Knuth: But that’s not the way he learned either. He said a lot of really great things and inspirational things, but he’s not always right. Neither am I, but my take on it is this: Take a scientist in any field. The scientist gets older and says, “Oh, yes, some of the things that I’ve been doing have a really great payoff and other things, I’m not using anymore. I’m not going to have my students waste time on the stuff that doesn’t make giant steps. I’m not going to talk about low-level stuff at all. These theoretical concepts are really so powerful—that’s the whole story. Forget about how I got to this point.”

I think that’s a fundamental error made by scientists in every field. They don’t realize that when you’re learning something you’ve got to see something at all levels. You’ve got to see the floor before you build the ceiling. That all goes into the brain and gets shoved down to the point where the older people forget that they needed it.

Coders at Work – Page 567 – Donald Knuth