Seibel: You’re an academic but also have worked on big systems and have done some work in industry. How do you see the relation between academic computer science and industrial practice?

Knuth: It’s gone in waves. In the ’60s the academics were way ahead of the industry and the programs that were produced in industry, except for maybe airline-reservation systems, were laughable to everybody in universities.

By 1980 the situation had pretty much reversed and the programs that were being written by people in universities were laughed at by the people in industry because the universities had gone into theological mode and you weren’t allowed to use goto statements. I’m exaggerating to simplify, but
basically there were no-nos in university programs that were keeping people’s hands tied, and the people in industry didn’t have to worry about that.

But then in universities people came up with some better ideas about networking and dealing with large pieces of data and so on, and got ahead. So it goes back and forth. But the trend in a lot of the algorithm and datastructure community has not been to my liking when they have lots of data
structures that are just . . . baroque is the only word I can think of. They’re intricate and clever and you have to admire them for the intellectual challenge, but I find them sterile. They don’t connect with life; they’re working in another world. It’s an OK world and it’s got its structure, and they’re friendly and nice people, but it doesn’t appeal to me personally and it doesn’t really relate to practice.

I don’t know why it’s important to me if something relates to practice or not. There are mathematicians who never think about anything finite, and they hardly ever come down to countably infinite—they publish terrific papers just talking about kinds of infinity that are mind-boggling and they’re
able to make sense out of it and that gives them satisfaction. And there are similar things like that in algorithms. But for me I’m turned on much more by the ideas that I would be able to use in my machine.

Coders at Work – Page 595 – Donald Knuth