3 ms·

Lining up this interview was a process that spanned the latter half of 2020. Professor Knuth has not maintained a public email inbox since 1990, so I typeset a

Lining up this interview was a process that spanned the latter half of 2020. Professor Knuth has not maintained a public email inbox since 1990, so I typeset a letter in LaTeX, printed it out, figured out where to put a stamp on an envelope, and sent it to Professor Knuth's office. Some months later, I received an email from his assistant, saying that he would be interested in doing an interview, but wouldn't be available until December. Well, a couple of weeks ago I found myself on the phone clutching a list of questions that I prepared in consultation with a friend of mine pursing a Ph.D. in computer science at the University of Chicago, and thus could understand not just the pictures in The Art of Computer Programming, but also most of the words (where my abilities begin to falter).

svat 6y ago
Thanks a lot for conducting this interview, transcribing it, and sharing it! It's lovely, and covers a lot of interesting/new ground; your questions are well-chosen. I've read/heard/watched a lot of Knuth interviews the last few years (there's a list of some of them at https://cs.stanford.edu/~knuth/news20.html#:~:text=Oral%20histories https://cs.stanford.edu/~knuth/news20.html#:~:text=Oral%20hi... and at https://tug.org/interviews/#knuth https://tug.org/interviews/#knuth), and he tends to be remarkably consistent in his answers, but you've managed to ask interesting questions that elicit new answers. :-) And of course even the repeated stuff is still interesting. Yes reaching him can be hard, as joked about by Wilf on his 64th birthday (https://www2.math.upenn.edu/~wilf/website/dek.pdf https://www2.math.upenn.edu/~wilf/website/dek.pdf). :-) If I understand correctly, this interview was conducted over the phone? If so, I also imagine that transcribing it must have been quite a bit of effort; his speech tends to have a fair bit of "backtracking" / "buffering" as I've found when I tried to transcribe something a while ago. So thanks for producing something so readable. Some notable (to me) highlights, for anyone else who has not yet read the linked interview: - The story of how The Art of Computer Programming came about. He was approached by the publisher in 1962 when he was a recently married second-year graduate student, to write a book about how to write compilers. He thought it needs more background and came up with a 12-chapter outline with Compilers as the final chapter, and thought it would be done before his son was born (1965), as of 2020 it's less than half done. :-) He actually had a handwritten manuscript of 3000 pages completed in early 1966 and thought that when printed it would be about 400 printed pages, but he was off and it would have been 2000 pages if printed. So the plan became 7 volumes. (He goes into more detail in his 2007 CHM Oral History for example: https://archive.computerhistory.org/resources/access/text/2013/05/102658053-05-01-acc.pdf#page=14&zoom=200,0,500 https://archive.computerhistory.org/resources/access/text/20...) - How he tries to make precise statements ("maximize my chance of error"), and writes programs to see for himself which methods are faster ("I can't write about something unless I've experienced it personally"). And how he does this while staying "smooth", adding technical jokes, and trying to be surprising! His motivation is always to share: "Isn't this cool?" - On staying motivated: his simple motivation is that he enjoys learning and enjoys telling others what he's learned. His main computer is also not connected to the internet; he goes to the internet-connected computer only to upload stuff. - He actually doesn't seem to worry at all about impact or importance; he just writes stuff that he needs or feels ought to exist. (I think his taste helps here!) He's unbothered by what others might consider failures of adoption (Metafont, literate programming, his composition Fantasia Apocalyptica?). - His usual thoughts on literate programming, e.g. "by taking a little bit of extra time to explain what the code is doing, I get my thoughts in order and I make many fewer mistakes". (Aside: He mentions the PBRT book (http://www.pbr-book.org/ http://www.pbr-book.org/) and thinks there is other software being written at Pixar/elsewhere using literate programming; does anyone know if this is actually true? Or is this program/book an exception?) - He mentions some problem in constraint satisfaction (the section of TAOCP he's currently working on) on pp 14–15, maybe someone can guess details of what this specific problem is? - One finding ways to enjoy what you're doing. (He's mentioned here, and elsewhere too, how he's never bored; how one can always find some way to enjoy things. Recall the example of buying janitor uniforms to make toilet-cleaning at home more fun! From an earlier article, discussed here: https://news.ycombinator.com/item?id=22889195 https://news.ycombinator.com/item?id=22889195) He's not bothered by commercialization/things being spoiled for example; he just focuses on what's beautiful and one can be proud of. (A few typos I noticed in the current version of the PDF: "Apocalypitca" (p1), "wonderfull" (p9), and in a few places, words are joined it appears that (probably) "—I" (an em dash followed by the word "I") turned into just "I": "I was blown awayI" (p3), "core memoryI" (p4), "practiceI" (p4). And the phrase "from two different slaps" (p6) sounds odd; sure he didn't say something else? Then again, maybe that's exactly what he said, things being slapped into one's brain.) Good luck with your book too!
- philipkiely 6y ago
  Asking questions that elicit new answers is the #1 thing I focus on in an interview, so I'm glad to have accomplished it here. I think that if you're doing an interview and don't cover new ground, it just wastes everyone's time. Asking new questions, just like transcribing, just requires focused effort! I think interviewing is a really cool skill because anyone can get good at it just with practice!
- gumby 6y ago
  > He's unbothered by what others might consider failures of adoption ...his composition Fantasia Apocalyptica... He somehow figured out I liked Bach and so a couple of years ago played me some of it (a recording) then we went over the score. He is a much better organ player than I could ever hope to be! Naturally the score was designed to reflect the book of revelation, so you could see elements of music that keyed off that text but it's sort of conventional and unconventional at the same time. It was fun to read as the music is sort of witty, but I don't think I'd enjoy listening to the whole thing. I've only known two people who had organs at home, Alan Kay and Don Knuth. Steve Jobs bought a house in Woodside that had an organ in it, but I heard he removed it. I never heard that he played music himself.
  - svat 6y ago
    Ha! On that composition: I have no ear for Western classical music, and familiarity with neither the organ as a musical instrument nor the Bible's Book of Revelation, but even so, I can guess this project is… unique. He calls it (https://cs.stanford.edu/~knuth/fant.html https://cs.stanford.edu/~knuth/fant.html) a "somewhat literal translation" of the book into music. So for example he goes over each verse of the book, and (almost) each time it mentions "angel" he plays an 8-note arpeggio, every time it mentions "blood" he has "coagulated" (clustered) notes, and so on, setting up "dictionary" of 100+ motifs (https://cs.stanford.edu/~knuth/motif-dict-utf8.html https://cs.stanford.edu/~knuth/motif-dict-utf8.html). He explains it in these videos (https://www.youtube.com/watch?v=-JvdanSygfg https://www.youtube.com/watch?v=-JvdanSygfg, https://www.youtube.com/watch?v=f1R9eY-8jL4 https://www.youtube.com/watch?v=f1R9eY-8jL4, https://www.youtube.com/watch?v=e_1a6bHGQGo https://www.youtube.com/watch?v=e_1a6bHGQGo). Looking through his list of musical allusions (https://cs.stanford.edu/~knuth/rev-cite https://cs.stanford.edu/~knuth/rev-cite) I see things like Bruce Springsteen, even a washing machine's power on/off cycle sound. He mentions a couple of pieces of rap music for verse Revelation 3:20; maybe the reason is the same joke as https://xkcd.com/133/ https://xkcd.com/133/? Overall, the project seems so crazy (is this the way anyone writes music?) that one can't help being impressed. The full performance is here: https://www.youtube.com/watch?v=MjxsZa3Ylao https://www.youtube.com/watch?v=MjxsZa3Ylao — haven't listened to it, but online I've seen both some extremely negative and some extremely positive comments. :-) I have heard that he is a skilled organ player as you said; just earlier while searching for something else I saw a blog post about Rajeev Motwani's memorial (http://blog.geomblog.org/2009/09/rajeev-motwani-memorial.html http://blog.geomblog.org/2009/09/rajeev-motwani-memorial.htm...) which mentions “Don Knuth was the organist for the entire ceremony, and played pieces you didn't think could be played on a church organ”.
deleted 6y ago
[deleted]
swyx 6y ago
that is an amazing story. once again you're showing how to hustle well beyond what most people think their limits are. well done.

svat 6y ago

Thanks a lot for conducting this interview, transcribing it, and sharing it! It's lovely, and covers a lot of interesting/new ground; your questions are well-chosen. I've read/heard/watched a lot of Knuth interviews the last few years (there's a list of some of them at https://cs.stanford.edu/~knuth/news20.html#:~:text=Oral%20histories https://cs.stanford.edu/~knuth/news20.html#:~:text=Oral%20hi... and at https://tug.org/interviews/#knuth https://tug.org/interviews/#knuth), and he tends to be remarkably consistent in his answers, but you've managed to ask interesting questions that elicit new answers. :-) And of course even the repeated stuff is still interesting. Yes reaching him can be hard, as joked about by Wilf on his 64th birthday (https://www2.math.upenn.edu/~wilf/website/dek.pdf https://www2.math.upenn.edu/~wilf/website/dek.pdf). :-) If I understand correctly, this interview was conducted over the phone? If so, I also imagine that transcribing it must have been quite a bit of effort; his speech tends to have a fair bit of "backtracking" / "buffering" as I've found when I tried to transcribe something a while ago. So thanks for producing something so readable. Some notable (to me) highlights, for anyone else who has not yet read the linked interview: - The story of how The Art of Computer Programming came about. He was approached by the publisher in 1962 when he was a recently married second-year graduate student, to write a book about how to write compilers. He thought it needs more background and came up with a 12-chapter outline with Compilers as the final chapter, and thought it would be done before his son was born (1965), as of 2020 it's less than half done. :-) He actually had a handwritten manuscript of 3000 pages completed in early 1966 and thought that when printed it would be about 400 printed pages, but he was off and it would have been 2000 pages if printed. So the plan became 7 volumes. (He goes into more detail in his 2007 CHM Oral History for example: https://archive.computerhistory.org/resources/access/text/2013/05/102658053-05-01-acc.pdf#page=14&zoom=200,0,500 https://archive.computerhistory.org/resources/access/text/20...) - How he tries to make precise statements ("maximize my chance of error"), and writes programs to see for himself which methods are faster ("I can't write about something unless I've experienced it personally"). And how he does this while staying "smooth", adding technical jokes, and trying to be surprising! His motivation is always to share: "Isn't this cool?" - On staying motivated: his simple motivation is that he enjoys learning and enjoys telling others what he's learned. His main computer is also not connected to the internet; he goes to the internet-connected computer only to upload stuff. - He actually doesn't seem to worry at all about impact or importance; he just writes stuff that he needs or feels ought to exist. (I think his taste helps here!) He's unbothered by what others might consider failures of adoption (Metafont, literate programming, his composition Fantasia Apocalyptica?). - His usual thoughts on literate programming, e.g. "by taking a little bit of extra time to explain what the code is doing, I get my thoughts in order and I make many fewer mistakes". (Aside: He mentions the PBRT book (http://www.pbr-book.org/ http://www.pbr-book.org/) and thinks there is other software being written at Pixar/elsewhere using literate programming; does anyone know if this is actually true? Or is this program/book an exception?) - He mentions some problem in constraint satisfaction (the section of TAOCP he's currently working on) on pp 14–15, maybe someone can guess details of what this specific problem is? - One finding ways to enjoy what you're doing. (He's mentioned here, and elsewhere too, how he's never bored; how one can always find some way to enjoy things. Recall the example of buying janitor uniforms to make toilet-cleaning at home more fun! From an earlier article, discussed here: https://news.ycombinator.com/item?id=22889195 https://news.ycombinator.com/item?id=22889195) He's not bothered by commercialization/things being spoiled for example; he just focuses on what's beautiful and one can be proud of. (A few typos I noticed in the current version of the PDF: "Apocalypitca" (p1), "wonderfull" (p9), and in a few places, words are joined it appears that (probably) "—I" (an em dash followed by the word "I") turned into just "I": "I was blown awayI" (p3), "core memoryI" (p4), "practiceI" (p4). And the phrase "from two different slaps" (p6) sounds odd; sure he didn't say something else? Then again, maybe that's exactly what he said, things being slapped into one's brain.) Good luck with your book too!

philipkiely 6y ago
Asking questions that elicit new answers is the #1 thing I focus on in an interview, so I'm glad to have accomplished it here. I think that if you're doing an interview and don't cover new ground, it just wastes everyone's time. Asking new questions, just like transcribing, just requires focused effort! I think interviewing is a really cool skill because anyone can get good at it just with practice!
gumby 6y ago
> He's unbothered by what others might consider failures of adoption ...his composition Fantasia Apocalyptica... He somehow figured out I liked Bach and so a couple of years ago played me some of it (a recording) then we went over the score. He is a much better organ player than I could ever hope to be! Naturally the score was designed to reflect the book of revelation, so you could see elements of music that keyed off that text but it's sort of conventional and unconventional at the same time. It was fun to read as the music is sort of witty, but I don't think I'd enjoy listening to the whole thing. I've only known two people who had organs at home, Alan Kay and Don Knuth. Steve Jobs bought a house in Woodside that had an organ in it, but I heard he removed it. I never heard that he played music himself.
- svat 6y ago
  Ha! On that composition: I have no ear for Western classical music, and familiarity with neither the organ as a musical instrument nor the Bible's Book of Revelation, but even so, I can guess this project is… unique. He calls it (https://cs.stanford.edu/~knuth/fant.html https://cs.stanford.edu/~knuth/fant.html) a "somewhat literal translation" of the book into music. So for example he goes over each verse of the book, and (almost) each time it mentions "angel" he plays an 8-note arpeggio, every time it mentions "blood" he has "coagulated" (clustered) notes, and so on, setting up "dictionary" of 100+ motifs (https://cs.stanford.edu/~knuth/motif-dict-utf8.html https://cs.stanford.edu/~knuth/motif-dict-utf8.html). He explains it in these videos (https://www.youtube.com/watch?v=-JvdanSygfg https://www.youtube.com/watch?v=-JvdanSygfg, https://www.youtube.com/watch?v=f1R9eY-8jL4 https://www.youtube.com/watch?v=f1R9eY-8jL4, https://www.youtube.com/watch?v=e_1a6bHGQGo https://www.youtube.com/watch?v=e_1a6bHGQGo). Looking through his list of musical allusions (https://cs.stanford.edu/~knuth/rev-cite https://cs.stanford.edu/~knuth/rev-cite) I see things like Bruce Springsteen, even a washing machine's power on/off cycle sound. He mentions a couple of pieces of rap music for verse Revelation 3:20; maybe the reason is the same joke as https://xkcd.com/133/ https://xkcd.com/133/? Overall, the project seems so crazy (is this the way anyone writes music?) that one can't help being impressed. The full performance is here: https://www.youtube.com/watch?v=MjxsZa3Ylao https://www.youtube.com/watch?v=MjxsZa3Ylao — haven't listened to it, but online I've seen both some extremely negative and some extremely positive comments. :-) I have heard that he is a skilled organ player as you said; just earlier while searching for something else I saw a blog post about Rajeev Motwani's memorial (http://blog.geomblog.org/2009/09/rajeev-motwani-memorial.html http://blog.geomblog.org/2009/09/rajeev-motwani-memorial.htm...) which mentions “Don Knuth was the organist for the entire ceremony, and played pieces you didn't think could be played on a church organ”.

deleted 6y ago

[deleted]

swyx 6y ago

that is an amazing story. once again you're showing how to hustle well beyond what most people think their limits are. well done.