knuth-interview-2006

age also tracks a few: http://www.softpanorama.org/People/Knuth/donald_knuth_interv... PS: The story that he told Steve Jobs he was "Full of shit" is not true. "Donald Knuth never told Steve Jobs that he was full of shit" https://news.ycombinator.com/item?id=2634635

write compilers. We’re going to put in a proposal to Burroughs to write a compiler for their machine, the Burroughs 205, for a language called ALGOL, which was just being invented at that time […] made a proposal to Burroughs for I believe it was $70,000, to create an ALGOL compiler for the Burroughs 205. The people who made this proposal really, though, were clueless about how to write compilers, so they hired me, a Case senior, to do the job, because they had heard that I knew how to do it. I had done this RUNCIBLE and a couple of versions of other software at Case, […] but Burroughs turned them down; they didn’t give them the contract. > So after Burroughs said no, […] maybe I’ll write to Burroughs on my own, and I sent them a letter and said, I’ll, you know, for $5,000 I can write you an ALGOL compiler. Now $5,000 was a huge amount of money in 1959, 1960. I mean a college professor was making $8,000 a year or something like this. So I thought $5,000 was an incredibly rich thing, you know, to do. […] > […] I spent the summer writing this compiler for ALGOL, for the Burroughs 205, and I wrote it, but really I had it only in pencil and paper, I didn’t have it ready to go, and then I would take it with me on, as I went out to Pasadena, and work on it there when I was at the Burroughs plant in Pasadena. > So on my way out West; I had a little Volkswagen, that I had gotten from my parents, and I drove 100 miles a day, and got a motel, and sat down, and wrote code, wrote software, and took 30 days to drive from Milwaukee to Pasadena, every day writing a little bit of this software. Then I got to Pasadena, and had all my code, had all my notes, and started putting it on to punched cards, and you know, debugging it and by Christmas time I had their compiler for them […] I heard for the next ten years that people in Brazil were still using it a lot. > And so it was a, it was an interesting experience for me, but the most important, from my point of view, was I had $5,500, which was enough to get married. And so in the summer of ‘61 Jill and I got married, and it paid for our honeymoon trip in Europe, which was our first time seeing the world. The actual compiler “source code” (written in pencil, assembly language and flowcharts) seems to be this one: http://archive.computerhistory.org/resources/text/Knuth_Don_... There's also 43-page “documentation” of the compiler http://archive.computerhistory.org/resources/text/Knuth_Don_... which starts with “How does this compiler work? Frankly, it's a miracle if it does”. Also in the same interview, he reveals something about how he ended up getting a master's degree (as mentioned in the story here): > […] second half of my freshman year, I started having a little problem with my grades, and so I had to give up ping-pong. > But starting in my sophomore — junior year, I found out that you could take graduate courses at Case, and they were easier than the undergraduate courses. The reason is that Case had really strict admissions requirements for undergrads, but they were fairly loose about admitting graduate students. […] > And as a result, I had accumulated also, by the time I was a senior, I had accumulated lots and lots of graduate credits. Now, as a result then, Case did, on Graduation Day, Case did an unprecedented thing that had never been done before, they awarded me a Master’s Degree, simultaneously with my Bachelor’s Degree. And this, the faculty had gotten together and [voted] unanimously that this should happen, and I remember, you know, that was another thing that got into the newspapers at the time […] I had taken these graduate courses because they were easier. I didn’t, I don’t know if I’ve ever told anybody else this before today, but that was one of the reasons I could do so many other things.

n it done. I'm far more skeptical that you could TDD a compiler written in assembly language that achieves the kind of performance this scenario implies. (But tests, especially regression tests, are extremely valuable for writing compilers.) The particular compiler we're talking about here was one Knuth wrote during a summer-long road trip for US$5500 (roughly US$120 000 today). So the situation was actually considerably more extreme than you're imagining — not only did he not have punch cards when he wrote the compiler, he'd never seen the computer. So he had to spend a few months debugging it after he actually finished driving to the other side of the continent where the computer was. https://github.com/kragen/knuth-interview-2006#27---writing-...

the earliest programs he wrote as an undergrad when he first encountered computers (https://www.youtube.com/watch?v=Q9JOrmgHw28): the programs themselves are here: https://www.computerhistory.org/collections/search/?s=X8738.... (in machine language / assembly) I've watched the Web of Stories one fully (and the others not yet fully)… they are a delight. You can see the way his mind works, and he's someone whose career has spanned basically the entirety of computer science as a separate academic discipline.

d, and that’s what gave me the confidence that I should think a little more about programming, because I might be, you know, I might be good at it."

w, he posted these numbers, and the Case News Service was always good at trying to plant interesting stories in the local paper, so they sent reporters out [...] and IBM heard about it. So IBM sent out [a camera crew] to make a film of me spotting a game, [...] our Case team playing basketball [...] how I would punch the cards, you know, and put it into the IBM computer. Before they took the shot of the IBM computer, they planted a great, big IBM sign on the machine, so that nobody could fail to miss it [...] and it’s getting printed out on the IBM printer, and then the Coach is looking at it and posting this up. > So this was a little movie that I was in, about two or three minutes long. IBM supplies this movie to CBS, and they put it on the Sunday Evening News with Walter Cronkite, and all my relatives in Florida can see me on TV. This was very exciting. Also US News and World Report ran a story about it, and so this was my connection between computing and sports, when I was at Case. This was also a clever way for IBM to get their advertisements in there, rather subtly, but it was fun. > That was when I first realized how hard it must be to be a movie star, because I had to walk through these scenes six times everything, you know, punch those cards over and over again. How could Audrey Hepburn possibly look so beautiful after the sixth take, you know? (Thanks to https://github.com/kragen/knuth-interview-2006 for transcribing the videos.)

d, our math program wasn’t much, and I had never heard of calculus until I got to college. But the calculus book that we had was great, and in the back of the book there were supplementary problems that weren’t, you know, that weren’t assigned by the teacher. The teacher would assign, so this was a famous calculus text by a man named George Thomas, and I mention it especially because it was one of the first books published by Addison-Wesley, and I loved this calculus book so much that later I chose Addison-Wesley to be the publisher of my own book. But Thomas’s Calculus would have the text, then would have problems, and our teacher would assign, say, the even numbered problems, or something like that. I would also do the odd numbered problems. In the back of Thomas’s book he had supplementary problems, the teacher didn’t assign the supplementary problems; I worked the supplementary problems. I was, you know, I was scared I wouldn’t learn calculus, so I worked hard on it, and it turned out that of course it took me longer to solve all these problems than the kids who were only working on what was assigned, at first. But after a year, I could do all of those problems in the same time as my classmates were doing the assigned problems, and after that I could just coast in mathematics, because I’d learned how to solve problems. So it was good that I was scared, in a way that I, you know, that made me start strong, and then I could coast afterwards, rather than always climbing and being on a lower part of the learning curve." [1] http://authenticinquirymaths.blogspot.pt/2015/11/maths-in-sc.... [2] Transcript from here: https://github.com/kragen/knuth-interview-2006

lems; I worked the supplementary problems. I was, you know, I was scared I wouldn’t learn calculus, so I worked hard on it, and it turned out that of course it took me longer to solve all these problems than the kids who were only working on what was assigned, at first. But after a year, I could do all of those problems in the same time as my classmates were doing the assigned problems, and after that I could just coast in mathematics, because I’d learned how to solve problems. So it was good that I was scared, in a way that I, you know, that made me start strong, and then I could coast afterwards, rather than always climbing and being on a lower part of the learning curve.

d, our math program wasn’t much, and I had never heard of calculus until I got to college. But the calculus book that we had was great, and in the back of the book there were supplementary problems that weren’t, you know, that weren’t assigned by the teacher. The teacher would assign, so this was a famous calculus text by a man named George Thomas, and I mention it especially because it was one of the first books published by Addison-Wesley, and I loved this calculus book so much that later I chose Addison-Wesley to be the publisher of my own book. But Thomas’s Calculus would have the text, then would have problems, and our teacher would assign, say, the even numbered problems, or something like that. I would also do the odd numbered problems. In the back of Thomas’s book he had supplementary problems, the teacher didn’t assign the supplementary problems; I worked the supplementary problems. I was, you know, I was scared I wouldn’t learn calculus, so I worked hard on it, and it turned out that of course it took me longer to solve all these problems than the kids who were only working on what was assigned, at first. But after a year, I could do all of those problems in the same time as my classmates were doing the assigned problems, and after that I could just coast in mathematics, because I’d learned how to solve problems. So it was good that I was scared, in a way that I, you know, that made me start strong, and then I could coast afterwards, rather than always climbing and being on a lower part of the learning curve." [1] http://authenticinquirymaths.blogspot.pt/2015/11/maths-in-sc... [2] Transcript from here: https://github.com/kragen/knuth-interview-2006