Guido van Rossum: Python

Guido van Rossum is the creator of Python, one of the most popular and impactful programming languages in the world. Video version is available on YouTube https://www.youtube.com/watch?v=ghwaIiE3Nd8. If you would like to get more information about this podcast go to https://lexfridman.com/ai or connect with @lexfridman on Twitter https://twitter.com/lexfridman, LinkedIn https://www.linkedin.com/in/lexfridman/, Facebook https://www.facebook.com/lexfridman, or YouTube https://www.youtube.com/lexfridman where you can watch the video versions of these conversations.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Lex Fridman?

  The following is a conversation with Guido van Rossum, creator of Python, one of the most popular programming languages in the world, used in almost any application that involves computers, from web backend development to psychology, neuroscience, computer vision, robotics, deep learning, natural language processing, and almost any subfield of AI. This conversation is part of MIT course on artificial general intelligence and the artificial intelligence podcast. If you enjoy it, subscribe on YouTube, iTunes, or your podcast provider of choice, or simply connect with me on Twitter at @LexFriedman, spelled F R I D. And now, here's my conversation with Guido van Rossum.

• 1:02Lex Fridman?

  You were born in the Netherlands in 1956. Your parents and the world around you was deeply impacted by World War II, as was my family from the Soviet Union. So with that context, what is your view of human nature? Are some humans inherently good and some inherently evil? Or do we all have both good and evil within us?

• 1:31Guido van Rossum?

  Ouch. I did not expect such a deep one. I guess we all have good and evil potential in us and a lot of it depends on circumstances and context.

• 1:49Lex Fridman?

  Out of that world, at least on the Soviet Union side in Europe, sort of out of suffering, out of challenge, out of that kind of set of traumatic events, often emerges beautiful art, music, literature. In an interview I read or heard, you said you enjoyed Dutch literature when you were a child. Can you tell me about the books that had an influence on you in your childhood?

• 2:17Guido van Rossum?

  Well, as a teenager, my favorite writer was, my favorite Dutch author was a guy named Willem Fredrik Hermans, whose writing, certainly his early novels, were all about sort of

• 2:38Guido van Rossum?

  uh ambiguous things that happened during World War II. I think he was a young adult during that time, and he wrote about it

• 2:52Guido van Rossum?

  a lot, and, and very interesting, very good books, I thought, I think.

• 2:57Lex Fridman?

  In a nonfiction way?

• 3:00Guido van Rossum?

  No, it was all fiction, but it was very much set in, in the ambiguous world of resistance against the Germans, where often you couldn't tell whether someone was truly in the resistance, or really a spy for the Germans. And, and some of the characters in his novels sort of crossed that line, and you never really find out what exactly happened.

• 3:31Lex Fridman?

  And in his novels, there's always a good guy and a bad guy, is the nature of good and evil, is it uh clear, there's a hero?

• 3:38Guido van Rossum?

  It's, no, his heroes are often more, his main characters are often anti-heroes. And, and, and so they're, they're not, not very heroic. They're, they're often, they

• 3:53Guido van Rossum?

  they fail at some level to accomplish their lofty goals.

• 3:58Lex Fridman?

  And looking at the trajectory through the rest of your life, has literature, Dutch, or English, or translation, had an impact

• 4:07Lex Fridman?

  outside the technical world that you existed in?

• 4:10Guido van Rossum?

  Hmm.

• 4:14Guido van Rossum?

  I still read novels. I don't think that it impacts me that much directly.

• 4:22Lex Fridman?

  Doesn't impact your work? It's just, it's a...

• 4:25Guido van Rossum?

  It's a separate world. My work is highly technical and sort of the world of art and literature doesn't really directly have any bearing on it.

• 4:36Lex Fridman?

  You don't think there's a creative element to the design? You know, some would say art, design of a language is art.

• 4:46Guido van Rossum?

  I'm not disagreeing with that. I'm just saying that sort of I don't feel direct influences from more traditional art on my own creativity.

• 4:58Lex Fridman?

  Right, of course, you don't feel doesn't mean it's not somehow deeply there in your subconscious.

• 5:04Guido van Rossum?

  Who knows?

• 5:05Lex Fridman?

  Who knows? So, let's go back to your early teens. Your hobbies were building electronic circuits, building mechanical models. What, if you can just put yourself back in the mind of that young Guido, 12, 13, 14, was that grounded in a desire to create a system, so to create something? Or was it more just tinkering? Just the joy of puzzle solving?

• 5:34Guido van Rossum?

  Uh, I think it was more the latter, actually. I, maybe towards the end of my high school period, I felt confident enough that I designed my own circuits that were sort of interesting somewhat. But a lot of that time, I literally just took a model kit and followed the instructions, putting the things together. I mean, I think the first few years that I built electronics kits, I really did not have enough understanding of sort of electronics to really understand what I was doing.

• 6:18Guido van Rossum?

  I mean, I could debug it and I could sort of follow the instructions very carefully, which has always stayed with me. But I had a very naive model of like how a transistor works.

• 6:34Guido van Rossum?

  And I don't think that in those days I had any understanding of coils and capacitors, which actually was a major problem when I started to build more complex digital circuits, because I was unaware of the analog part of how they actually work. And I would have things that... The schematic looked... Everything looked fine, and it didn't work. And what I didn't realize was that there was some megahertz level oscillation that was

• 7:17Guido van Rossum?

  throwing the circuit off, because I had a... Sort of two wires were too close, or the switches were kind of poorly built.

• 7:29Lex Fridman?

  But through that time, I think it's really interesting and instructive to think about, because echoes of it are in this time now. So in the 1970s, the personal computer was being born. So did you sense, in tinkering with these circuits, did you sense the encroaching revolution in personal computing? So if at that point, we sit you down and ask you to predict the 80s and the 90s, do you think you would be able to do so successfully to unroll the process that's happened?

• 8:06Guido van Rossum?

  No, I had no clue. I remember, I think, in the summer after my senior year, or maybe it was the summer after my junior year. Well, at some point, I think, when I was 18, I went on a trip.

• 8:25Guido van Rossum?

  To the Math Olympiad in Eastern Europe. And there was like, I was part of the Dutch team. And there were other nerdy kids that sort of had different experiences. And one of them told me about this amazing thing called a computer. And I had never heard that word. My, my own explorations in electronics were sort of about very simple digital circuits. And I, I had sort of, I had the idea that I somewhat understood how a digital calculator worked. And so there is maybe some echoes of computers there, but I didn't, didn't, I never made that connection.

• 9:09Guido van Rossum?

  I didn't know that when my parents were paying for magazine subscriptions using punched cards, that there was something called a computer that was involved that read those cards and transferred the money between accounts. I was also not really interested in those things. It was only when I went to university to study math that I found out that they had a computer and students were allowed to use it.

• 9:39Lex Fridman?

  And there were some, you're supposed to talk to that computer by programming it. What did that feel like?

• 9:45Guido van Rossum?

  That was the, yeah, that was the only thing you could do with it. The, the computer wasn't really connected to the real world. The only thing you could do was sort of, you typed your program on a bunch of punched cards. You gave the punched cards to the operator. And an hour later, the operator gave you back your printout. And so all you could do was write a program that did something very abstract. And I don't even remember what my first forays into programming were, but.

• 10:23Guido van Rossum?

  They were sort of doing simple math exercises and just to learn how a programming language worked.

• 10:31Lex Fridman?

  Did you sense, okay, first year of college, you see this computer, you're able to have a program and it generates some output. Did you start seeing the possibility of this? Or was it a continuation of the tinkering with circuits? Did you start to imagine that, one, the personal computer, but did you see it as something that is a tool? It's like a tool, like a word processing tool, maybe for gaming or something? Or did you start to imagine that it could be, you know, going to the world of robotics? Like, you know, the Frankenstein picture that you could create an artificial being, there's like another entity in front of you. You did not see-

• 11:15Guido van Rossum?

  I don't think I really saw it that way. I was really more interested in the tinkering. It's maybe not as sort of a complete coincidence that I ended up sort of creating a programming language, which is a tool for other programmers. I've always been very focused on the sort of activity of programming itself and not so much what happens with the program you write.

• 11:45Lex Fridman?

  Right.

• 11:46Guido van Rossum?

  I do remember, and I don't reme- maybe in my second or third year, probably my second actually, someone pointed out to me that there was this thing called Conway's Game of Life. You're probably familiar with it.

• 12:06Guido van Rossum?

  I think-

• 12:06Lex Fridman?

  In the seventies, I think, is when he came up with it.

• 12:09Guido van Rossum?

  So there was a Scientific American column by someone who did a monthly column about mathematical diversions. I'm also blanking out on the guy's name. It was very famous at the time and I think up to the nineties or so. And one of his columns was about Conway's Game of Life and he had some illustrations and he wrote down all the rules. And sort of there was the suggestion that this was philosophically interesting, that that was why Conway had called it that.

• 12:42Guido van Rossum?

  And all I had was like the two pages photocopy of that article. I didn't even remember where I got it. Uh, but it spoke to me and I remember implementing a version of that game

• 12:59Guido van Rossum?

  for the batch computer we were using where I had a whole Pascal program that sort of read an initial situation from input and read some numbers that that said, do so many generations and print every so many generations. And then out would come pages and pages of of sort of things.

• 13:24Lex Fridman?

  Patterns of different kinds and yeah.

• 13:26Guido van Rossum?

  Yeah. And I remember much later I've done a similar thing using Python, but I'd sort of that original version I wrote at the time. I found interesting because I combined it with some trick I had learned during my electronics hobbyist times. I essentially first on paper, I designed a simple circuit built out of logic gates that took nine bits of input, which is the sort of the cell and its neighbors

• 14:04Guido van Rossum?

  and produce the new value for that cell. And it's like a combination of of a half adder and some other clipping. No, it's actually a full adder. And so I had worked that out and then I translated that into a series of Boolean operations on Pascal integers where you could use the integers as bitwise uh, values. And so I could basically generate 60 bits of a generation in a, in like.

• 14:43Guido van Rossum?

  Eight instructions or so.

• 14:45Lex Fridman?

  Nice.

• 14:46Guido van Rossum?

  So I was proud of that.

• 14:48Lex Fridman?

  It's funny that you mentioned, so for people who don't know Conway's Game of Life is a there's it's a cellular automata where there's single compute units that kind of look at their neighbors and figure out what they look like in the next generation based on the state of their neighbors and this is deeply distributed system in in concept at least and then there's simple rules that all of them follow and somehow out of this simple rule when you step back and look at what occurs it's it's beautiful there's a emergent complexity even though the underlying rules are simple there's an emergent complexity now the funny thing is you've implemented this

• 15:33Lex Fridman?

  and the thing you're commenting on is you're proud of a hack you did to make it run efficiently where you're not commenting on what like this is a beautiful implementation you're not commenting on the fact that there's an emergent complexity that you've you've you've coded a simple program and when you step back and you print out this following generation after generation that's stuff that you may have not predicted would happen is happening.

• 16:03Guido van Rossum?

  Right.

• 16:04Lex Fridman?

  And was that is that magic I mean that's the magic that all of us feel when we program when you create a program and then you run it and whether it's hello world or it shows something on screen if there's a graphical component are you seeing the magic in the mechanism of creating that?

• 16:21Guido van Rossum?

  I think I went back and forth as a student we had an incredibly small budget of computer time that we could use it was actually measured I once got in trouble with one of my professors because I had overspent the department's budget it's a different story but so.

• 16:44Guido van Rossum?

  I actually wanted the efficient implementation because I also wanted to explore what would happen with a larger number of generations and a larger sort of size of the board. And so, once the implementation was flawless, I would feed a different patterns and then I think maybe there was a follow-up article where there were patterns that were like gliders, patterns that repeated themselves after a number of generations but translated one

• 17:27Guido van Rossum?

  or two positions to the right or up or something like that. And there were, I remember things like glider guns. Well, you can Google Conway's Game of Life. It is still, people still go awe and ooh over it.

• 17:43Lex Fridman?

  For a reason, because it's not really well-understood. Why, I mean, this is what Stephen Wolfram is obsessed about. He's just, we don't have the mathematical tools to describe the kind of complexity that emerges in these kinds of systems. The only way you can do it is to run it.

• 18:01Guido van Rossum?

  I'm not convinced that it's sort of a problem that lends itself to classic mathematical analysis.

• 18:12Lex Fridman?

  No. And so, one theory of how you create an artificial intelligence or an artificial being is you kind of have to, same with the game of life, you kind of have to create a universe and let it run. That creating it from scratch in a design way, in a, you know, coding up a Python program that creates a fully intelligent system may be quite challenging, that you might need to create a universe, just like the game of life is.

• 18:43Guido van Rossum?

  Well, you might have to experiment with a lot of different universes before. There is a set of rules that doesn't essentially always just end up repeating itself in a trivial way.

• 18:58Lex Fridman?

  Yeah, and Stephen Wolfram works with these simple rules. Says that it's kind of surprising how quickly you find rules that create interesting things. You shouldn't be able to, but somehow you do. And so maybe our universe is laden with rules that will create interesting things. They might not look like humans, but you know, emergent phenomena that's interesting may not be as difficult to create as we think.

• 19:25Guido van Rossum?

  Sure.

• 19:26Lex Fridman?

  But let me sort of ask, at that time, you know, some of the world, at least in popular press,

• 19:33Lex Fridman?

  was kind of captivated, perhaps at least in America, by the idea of artificial intelligence. That these computers would be able to think pretty soon. And did that touch you at all? Did that, in science fiction or in reality, in any way?

• 19:53Guido van Rossum?

  I didn't really start reading science fiction until much, much later.

• 20:02Guido van Rossum?

  I think as a teenager, I read maybe one bundle of science fiction stories.

• 20:10Lex Fridman?

  Was it in the background somewhere, like in your thoughts?

• 20:13Guido van Rossum?

  That sort of the, using computers to build something intelligent always fell to me because I had, I felt I had so much understanding of what actually goes on inside a computer. I knew how many bits of memory it had and how difficult it was to program and sort of...

• 20:38Guido van Rossum?

  I didn't believe at all that that you could just build something intelligent out of that, that that would really sort of satisfy my definition of intelligence. I think the most influential thing that I read in my early twenties was Gödel, Escher, Bach. That was about consciousness and that was a big eye opener in some sense.

• 21:09Lex Fridman?

  In what sense? So, yeah, so on your own brain, did you at the time, or do you now see your own brain as a computer? Or is there a total separation of the way? So yeah, you're very pragmatically, practically know the limits of memory, the limits of this sequential computing, or weakly paralyzed computing, and you just know what we have now, and it's hard to see how it creates. But it's also easy to see, it was in the 40s, 50s, 60s, and now at least similarities between the brain and our computers.

• 21:47Guido van Rossum?

  Oh yeah, I mean, I totally believe that brains are computers in some sense. I mean, the rules they use to play by are pretty different from the rules we can sort of implement in our current hardware. But I don't believe in like, a separate thing that infuses us with intelligence, or consciousness, or any of that. There's no soul. I've been an atheist

• 22:26Guido van Rossum?

  probably from when I was 10 years old, just by thinking a bit about math and the universe. Well, my parents were atheists. Now, I know that you could be an atheist and still believe that there is something sort of about intelligence or consciousness that cannot possibly emerge from a fixed set of rules. I am not in that camp. I totally see that.

• 23:00Guido van Rossum?

  Sort of given how many millions of years evolution took its time. DNA is is a particular machine that that sort of encodes information and an unlimited amount of information in in chemical form and has figured out a way to replicate itself. I thought that that was maybe it's 300 million years ago, but I thought it was closer to half a half a billion years ago that that's sort of originated and it hasn't really changed

• 23:41Guido van Rossum?

  that the sort of the structure of DNA hasn't changed ever since. That is like our binary code that we have in hardware. I mean,

• 23:51Lex Fridman?

  The basic programming language hasn't changed, but maybe the programming itself.

• 23:56Guido van Rossum?

  Obviously did did sort of it. It happened to be a set of rules that was good enough to to sort of develop endless variability and and sort of the the idea of self replicating molecules competing with each other for resources and and one type eventually sort of always taking over. That happened before there were any fossils. So we don't know how that exactly happened, but I believe it's it's clear that that did happen and.

• 24:35Lex Fridman?

  Can you comment on consciousness and how you see it? Because I think we'll talk about programming quite a bit. We'll talk about, you know, intelligence connecting to programming fundamentally, but consciousness consciousness is this whole other other thing. Do you think about it often as a developer of a programming language? And and as a human?

• 25:01Guido van Rossum?

  Those those are pretty sort of separate topics. My sort of my line of work, working with programming does not involve anything that that goes in the direction of developing intelligence or consciousness, but sort of privately as an avid reader of popular science writing.

• 25:28Guido van Rossum?

  I have some thoughts which is mostly that I don't actually believe that consciousness is an all or nothing thing. I have a feeling that, and I forget what I read that influenced this, but I feel that if you look at a cat or a dog or a mouse, they have some form of intelligence. If you look at a fish, it has some form of intelligence. And

• 26:07Guido van Rossum?

  that evolution just took a long time, but I feel that the sort of the evolution of more and more intelligence that led to to sort of the human form of intelligence followed the evolution of the senses, especially the visual sense. I mean, there is an enormous amount of processing that's needed to interpret a scene. And humans are still better at that than than computers are.

• 26:42Lex Fridman?

  Yeah.

• 26:43Guido van Rossum?

  And and I have a feeling that there is a sort of the reason that that like mammals is in particular developed the levels of consciousness that they have and that eventually read sort of in from going from intelligence to to self-awareness and consciousness has to do with sort of being a robot that has very highly developed senses.

• 27:14Lex Fridman?

  Has a lot of rich sensory information coming in. So the that's a really interesting thought that the

• 27:23Lex Fridman?

  That whatever that basic mechanism of DNA, whatever that basic building blocks of programming is you, if you just add more abilities, more, more high resolution sensors, more sensors, you just keep stacking those things on top that this basic programming in trying to survive develops very interesting things that start to us humans to appear like intelligence and consciousness.

• 27:48Guido van Rossum?

  Yeah, so in, in, as far as robots go, I think that the self-driving cars have that sort of, the greatest opportunity of developing something like that because when I drive myself, I don't just pay attention to the rules of the road. I also look around and I get clues from that, oh, this is a shopping district. Oh, here's an old lady crossing the street. Oh, here is someone carrying a pile of mail. There's a mailbox. I bet you they're gonna cross the street to reach that mailbox. And I slow down and I don't even think about that.

• 28:32Lex Fridman?

  Yep.

• 28:33Guido van Rossum?

  And, and so there is, there is so much where you turn your observations into an understanding of what other consciousnesses are going to do, or what, what other systems in the world are going to be, oh, that tree is gonna fall.

• 28:51Lex Fridman?

  Yeah.

• 28:52Guido van Rossum?

  I, I, I see sort of, I see much more of, I, I expect somehow that if anything is going to become conscious, it's going to be the self-driving car and not the network of a bazillion computers at, in a Google or Amazon data center that are all networked together to, to do whatever they do.

• 29:19Lex Fridman?

  So in that sense, so you actually highlight, that's what I work in is in autonomous vehicles, you highlight the big gap between what we currently can't do and what we truly need to be able to do to solve the problem. Under that formulation, then consciousness and intelligence is something that basically a system should have in order to interact with us humans, as opposed to some kind of abstract notion of.

• 29:49Lex Fridman?

  Consciousness. Consciousness is something that you need to have to be able to empathize, to be able to fear, to understand what the fear of death is. All these aspects that are important for interacting with pedestrians, you need to be able to do basic computation based on our human desires and flaws.

• 30:13Guido van Rossum?

  If sort of, yeah, if you, if you look at the dog, the dog clearly knows, I mean, I'm not the dog owner, but I, I have friends who have dogs. The dogs clearly know what the humans around them are going to do, or at least they have a model of what those humans are going to do, and they learn. The do-, some dogs know when you're going out, and they want to go out with you. They're sad when you leave them alone, they cry. They're afraid because they were mistreated when they were younger.

• 30:46Guido van Rossum?

  We, we don't assign sort of consciousness to dogs, or at least not, not all that much, but I, I also don't think they have none of that. So I think it's, it's, consciousness and intelligence are not all or nothing.

• 31:06Lex Fridman?

  It's a spectrum. It's really interesting. But in returning to programming languages and the way we think about building these kinds of things, about building intelligence, building consciousness, building artificial beings. So I think one of the exciting ideas came in the 17th century, and with Leibniz, Hobbes, Descartes, where there's this feeling that you can convert all thought, all reasoning, all the thing that we find very special in our brains, you can convert all of that into logic. You can formalize it, formal reasoning. And then, once you formalize everything, all of knowledge, then you can just calculate. And that's what we're doing with our brains, is we're calculating.

• 31:51Lex Fridman?

  So there's this whole idea that we, that this is possible, that this.

• 31:56Guido van Rossum?

  But they weren't aware of the concept of pattern matching in the sense that we are aware of it now. They sort of thought you, they, they had discovered incredible bits of mathematics, like Newton's calculus.

• 32:13Guido van Rossum?

  And their sort of idealism, their their sort of extension of what they could do with logic and math sort of went along those lines. And they thought there's there's like, yeah, logic. There's there's like a bunch of rules and a bunch of input. They didn't realize that how you recognize a face is not just a bunch of rules, but is a shit ton of data. Plus, a circuit that that sort of interprets the visual clues and the context and everything else.

• 32:57Guido van Rossum?

  And somehow can massively parallel pattern match against stored rules. I mean, if I see you tomorrow here in front of the Dropbox office, I might recognize you.

• 33:12Lex Fridman?

  Even if I'm wearing a different shirt.

• 33:14Guido van Rossum?

  Yeah, but if I if I see you tomorrow in a coffee shop in Belmont, I might have no idea that it was you or on the beach or whatever. I make those kind of mistakes myself all the time. I see someone that I only know as like, oh, this person is a colleague of my wife's. And then I see them at the movies and I don't recognize them.

• 33:36Lex Fridman?

  But do you see those you call it pattern matching? Do you see that rules is unable to encode that to you? Everything you see, all the piece of information, you look around this room. I'm wearing a black shirt. I have a certain height. I'm a human, all these you can. There's probably tens of thousands of facts you pick up moment by moment about this scene. You take them for granted and you accumulate aggregate them together to understand the scene. You don't think all of that could be encoded to where at the end of the day, you can just put it all on the table and calculate?

• 34:12Guido van Rossum?

  Oh, I don't know what that means. I mean, yes, in the sense that there is no there. There is no actual magic there, but there are enough layers of abstraction from sort of from the facts as they enter my eyes and my ears to the understanding of the scene that that's I don't think that that AI has really covered enough of of.

• 34:43Guido van Rossum?

  Of that distance. It's like if you take a human body and you realize it's built out of atoms. Well, that that is a uselessly reductionist view, right?

• 34:57Lex Fridman?

  Right.

• 34:58Guido van Rossum?

  The body is built out of organs, the organs are built out of cells, the cells are built out of proteins, the proteins are built out of amino acids, the amino acids are built out of atoms, and then you get to quantum mechanics.

• 35:14Lex Fridman?

  So that's a very pragmatic view. I mean, obviously, as an engineer, I agree with that kind of view, but I also you also have to consider the the with the Sam Harris view of, well, well, intelligence is just information processing. You just, like you said, you take in sensory information, you you do some stuff with it, and you come up with actions that are intelligent.

• 35:36Guido van Rossum?

  That make he makes it sound so easy. I don't know who Sam Harris is.

• 35:40Lex Fridman?

  Uh, oh, uh, well, it's philosopher. So like this is how philosophers often think, right? And and essentially, that's what Descartes was is, wait a minute, if there is, like you said, no magic. So he basically says, it doesn't appear like there's any magic, but we know so little about it that it might as well be magic. So ju- just because we know that we're made of atoms, just because we know we're made of organs, the fact that we know very little how to get from the atoms to organs in a way that's recreatable means it that you shouldn't get too excited just yet about the fact that you figured out that we're made of atoms.

• 36:18Guido van Rossum?

  Right. And and and the same about taking facts as our our sensory organs take them in and turning that into reasons and actions. That sort of there are a lot of abstractions that we haven't quite figured out how to how to deal with those. I mean, I.

• 36:43Guido van Rossum?

  Sometimes, I don't know if I can go on a tangent or not. Please, drag you back in. Sure, so if I take a simple program that parses, say I have a compiler, it parses a program. In a sense, the input routine of that compiler, of that parser, is a sensing organ. And it builds up a mighty complicated internal representation of the program it just saw. It doesn't just have a linear sequence of bytes representing the text of the program anymore. It has an abstract syntax tree.

• 37:25Guido van Rossum?

  And I don't know how many of your viewers or listeners are familiar with compiler technology, but there's... Fewer and fewer these days, right? Uh, that's also true, probably. People want to take a shortcut, but there's sort of... This abstraction is a data structure that the compiler then uses to produce outputs that is relevant, like a translation of that program to machine code that can be executed by hardware.

• 38:01Guido van Rossum?

  And then that data structure gets thrown away. When a fish or a fly sees, sort of gets visual impulses, I'm sure it also builds up some data structure. And for the fly, that may be very minimal. A fly may, may have only a few... I mean, in the case of a fly's brain, I could imagine that there are few enough layers of abstraction that it's not much more than when it's darker here than it is here. Well, it can sense motion, because a fly sort of responds when you move your arm towards it.

• 38:46Guido van Rossum?

  So clearly, its visual processing is intelligent, well, not intelligent, but it has an abstraction for motion. And we still have similar things in, but much more complicated in our brains. I mean, otherwise, you couldn't drive a car if you couldn't sort, if you didn't have an incredibly good abstraction for motion.

• 39:10Lex Fridman?

  Yeah, in some sense, the same abstraction from motion is probably one of the primary sources of our of information for us. We just know what to do. I think we know what to do with that. We've built up other abstractions on top.

• 39:24Guido van Rossum?

  We build much more complicated data structures based on that, and we build more persistent data structures, sort of after some processing, some information sort of gets stored in our memory pretty much permanently and is available on recall. I mean, there are some things that you sort of, you're conscious that you're remembering it. Like, you give me your phone number, I, well, at my age, I have to write it down, but I could imagine I could remember those seven numbers or 10 digits and reproduce them in a while if I sort of repeat them to myself a few times. So that's a fairly conscious form of memorization. On the other

• 40:09Guido van Rossum?

  hand, how do I recognize your face? I have no idea. My brain has a whole bunch of specialized hardware that knows how to recognize faces. I don't know how much of that is sort of coded in our DNA and how much of that is trained over and over between the ages of zero and three. But somehow, our brains know how to do lots of things like that that are useful in our interactions with other humans without really being conscious of how it's done anymore.

• 40:45Lex Fridman?

  Right. So our actual day-to-day lives, we're operating at the very highest level of abstraction. We're just not even conscious of all the little details underlying it. There's compilers on top of, it's like turtles on top of turtles, or turtles all the way down, it's compilers all the way down. But that's essentially, you say that there's no magic. That's what.

• 41:07Lex Fridman?

  What I was trying to get at, I think, is when Descartes started this whole train of saying that there's no magic. I mean, there's others before him.

• 41:15Guido van Rossum?

  Well, didn't Descartes also have the notion, though, that the soul and the body were fundamentally separate?

• 41:22Lex Fridman?

  Yeah, I think he had to write in God in there for political reasons. So I don't actually, I'm not a historian, but there's notions in there that all of reasoning, all of human thought can be formalized. I think that continued in the 20th century with Russell and with Gödel's incompleteness theorem, this debate of what are the limits of the things that could be formalized. That's where the Turing machine came along and this exciting idea, I mean, underlying a lot of computing, that you can do quite a lot with a computer. You can encode a lot of the stuff we're talking about in terms of recognizing faces and so

• 42:03Lex Fridman?

  on theoretically, in an algorithm that can then run on a computer. And in that context, I'd like to ask, programming in a philosophical way, what does it mean to program a computer? So you said you write a Python program or a compiled, a C++ program that compiles to some bytecode. It's forming layers. You're programming a layer of abstraction that's higher. How do you see programming in that context? Can it keep getting higher and higher levels of abstraction?

• 42:44Guido van Rossum?

  I think at some point, the higher levels of abstraction will not be called programming, and they will not resemble what we call programming at the moment. There will not be source code. I mean, there will still be source code, sort of, at a lower level of the machine, just like there are still molecules and electrons and sort of proteins in our brains.

• 43:18Guido van Rossum?

  But and and so there's still programming and and and system administration and who knows what keeping to keep the machine running. But what the machine does is is a different level of abstraction in a sense. And as far as I understand, the way that for last decade or more people have made progress with things like facial recognition or the self-driving cars is all by endless, endless amounts of training data where

• 43:52Guido van Rossum?

  at least as as as a layperson, and I feel myself totally as a layperson in that field, it looks like

• 44:02Guido van Rossum?

  the researchers who published the results don't necessarily know exactly how how their algorithms work. And I often get upset when I sort of read a sort of a fluff piece about Facebook in the newspaper or social networks and they say, well, algorithms. And that's like a totally different interpretation of the word algorithm.

• 44:30Lex Fridman?

  Yeah.

• 44:30Guido van Rossum?

  Because for me, the way I was trained or what I learned when I was eight or 10 years old, an algorithm is a set of rules that you completely understand, that can be mathematically analyzed and and and you can prove things. You can like prove that Aristotelian sieve produces all prime numbers and only prime numbers.

• 44:54Lex Fridman?

  Yeah. So I don't know if you know who Andre Karpati is.

• 44:58Guido van Rossum?

  I'm afraid not.

• 44:59Lex Fridman?

  So he's a head of AI at Tesla now, but he was at Stanford before. And he has this cheeky way of calling this concept software 2.0. So let me disentangle that for a second. So so kind of what you're referring to is the traditional, traditional, the the algorithm, the concept of an algorithm, something that's there. It's clear. You can read it. You understand it. You can prove its functioning is kind of software 1.0. And what software 2.0 is is exactly what you describe, which is you have neural networks, which is a type of machine learning that you feed a bunch of data and that neural network learns to do

• 45:44Lex Fridman?

  a function. All you specify is the inputs and the outputs you want, and you can't look inside. You can't analyze it. All you can do is train this function to map the inputs to the outputs by giving a lot of data. In that sense, programming becomes getting a lot of cleaning, getting a lot of data. That's what programming is in this.

• 46:05Guido van Rossum?

  Well, that would be programming 2.0.

• 46:07Lex Fridman?

  2.0, to programming 2.0.

• 46:09Guido van Rossum?

  And I, I wouldn't call it that programming. It's just a different activity, just like building organs out of cells is not called chemistry.

• 46:19Lex Fridman?

  Well, so let's just, let's just step back and think sort of more generally, of course. But, you know, it's like, as a parent, teaching, teaching your kids, things can be called programming. In that same sense, that that's how program has been used. You're providing them data, examples, use cases. So imagine writing a function not by, not with for loops and clearly readable text, but more saying, well, here's a lot of examples of what this function should take. And here's a lot of examples of when it takes those functions, it should do this.

• 47:04Lex Fridman?

  And then figure out the rest. So that's the 2.0 concept. And so the question I have for you is like, it's a very fuzzy way. This is the reality of a lot of these pattern recognition systems and so on. It's a fuzzy way of quote unquote programming. What do you think about this kind of world? Should it be called something totally different than programming? It's like if you're a software engineer, does that mean you're, you're designing systems that are very, can be systematically tested, evaluated, they have a very specific specification? And then this other fuzzy software 2.0 world, machine learning world, that's, that's something else totally?

• 47:49Lex Fridman?

  Or is there some intermixing that's possible?

• 47:56Guido van Rossum?

  Well, the question is probably only being asked because we don't quite know what that software 2.0 actually is. And it sort of, I think there is a truism that every task that AI has tackled in the past, at some point, we realized how it was done, and then it was no longer considered part of artificial intelligence, because it was no longer necessary to use that term. It was just, oh, now we know how to do this.

• 48:37Guido van Rossum?

  And a new field of science or engineering has been developed. And I don't know if sort of every form of learning or sort of controlling computer systems should always be called programming. So I don't know, maybe I'm focused too much on the terminology. But I expect that that there just will be different concepts where people with sort of different education and a different model of what they're trying to do will develop those concepts.

• 49:22Lex Fridman?

  Yeah, and I guess if you could comment on another way to put this concept is, I think, I think the kind of functions that neural networks provide is things, as opposed to being able to upfront prove that this should work for all cases you throw at it. All you're able, it's the worst case analysis versus average case analysis. All you're able to say is, it seems on everything we've tested to work 99.9% of the time, but we can't guarantee it, and it fails in unexpected ways. We can't even give you examples of how it fails in unexpected ways. But it's like really good most of the time.

• 50:06Guido van Rossum?

  Yeah.

• 50:07Lex Fridman?

  Is there no room for that in current ways we think about programming?

• 50:16Guido van Rossum?

  Programming 1.0 is actually sort of

• 50:22Guido van Rossum?

  getting to that point too, where the sort of the ideal of a bug-free program has been abandoned long ago by most software developers. We only care about bugs that manifest themselves often enough to be annoying. And we're willing to take the occasional crash or outage or incorrect result

• 50:55Guido van Rossum?

  for granted, because we can't possibly we don't have enough programmers to make all the code bug-free and it would be an incredibly tedious business. And if you try to throw formal methods at it, it gets it becomes even more tedious. So every once in a while, the user clicks on a link in and somehow they get an error. And the average user doesn't panic, they just click again and see if it works better the second time, which often magically it does. Or they go up and they try some other way of performing their task. So

• 51:39Guido van Rossum?

  that's sort of an end-to-end recovery mechanism and inside systems, there is all sorts of retries and timeouts and fallbacks. And I imagine that that sort of biological systems are even more full of that because otherwise they wouldn't survive.

• 52:02Lex Fridman?

  Do you think programming should be taught and thought of as exactly what you just said? I come from this kind of

• 52:13Lex Fridman?

  you're you're almost denying that fact always.

• 52:17Guido van Rossum?

  In in sort of basic programming education.

• 52:24Guido van Rossum?

  The sort of, the programs you're, you're having students write are so small and simple that if there is a bug, you can always find it and fix it. Because the sort of programming as it's being taught in some even elementary, middle schools, in high school, introduction to programming classes in college typically, it's programming in the small. Very few classes sort of actually teach software engineering, building large systems. I mean, every summer here at Dropbox, we have a large number of interns.

• 53:07Guido van Rossum?

  Every tech company on the west coast has the same thing. These interns are always amazed because this is the first time in their life that they see what goes on in a really large software development environment. And everything they've learned in college was almost always about a much smaller scale. And somehow that difference in scale makes a qualitative difference in how you, how you do things and how you think about it.

• 53:45Lex Fridman?

  If you then take a few steps back into decades of seventies and eighties, when you were first thinking about Python or just that world of programming languages, did you ever think that there would be systems as large as underlying Google, Facebook and Dropbox? Did you, when you were thinking about Python?

• 54:07Guido van Rossum?

  I was actually always caught by surprise by sort of this.

• 54:11Lex Fridman?

  Every stage of it.

• 54:12Guido van Rossum?

  Yeah, pretty much every stage of computing.

• 54:15Lex Fridman?

  So maybe just because you've spoken in other interviews, but I think the evolution of programming languages are fascinating and it's especially because it leads from my perspective towards greater and greater degrees of intelligence. I learned the first programming language I played with in Russia was with the turtle logo.

• 54:39Guido van Rossum?

  Logo, yeah.

• 54:40Lex Fridman?

  And if you look, I just have a list of programming languages, all of which I've no played with a little bit. And they're all beautiful in different ways from Fortran, COBOL, Lisp, ALGOL 60, BASIC, Logo again, C. There's a few, the object oriented came along in the 60s, Simula, Pascal, Smalltalk. All of that leads.

• 55:04Guido van Rossum?

  They're all the classics.

• 55:05Lex Fridman?

  The classics, yeah, the classic hits, right? Scheme, that's built on top of Lisp, on the database side SQL, C++ and all that leads up to Python, Pascal too. And that's before Python, MATLAB, these kind of different communities, different languages. So can you talk about that world? I know that sort of Python came out of ABC, which I actually never knew that language. I just, having researched this conversation, went back to ABC and it looks remarkably, it has a lot of annoying qualities, but underneath those, like all caps and so on. But underneath that, there's elements of Python that are quite,

• 55:50Lex Fridman?

  they're already there.

• 55:51Guido van Rossum?

  That's where I got all the good stuff.

• 55:53Lex Fridman?

  All the good stuff. So but in that world, you're swimming these programming languages. Were you focused on just the good stuff in your specific circle? Or did you have a sense of what, what is everyone chasing? You said that every programming language is built to scratch and itch.

• 56:13Lex Fridman?

  Were you aware of all the itches in the community? And if not, or if yes, I mean, what itch were you trying to scratch with Python?

• 56:21Guido van Rossum?

  Well, I'm glad I wasn't aware of all the itches because I would probably not have been able to do anything. I mean, if you're trying to solve every problem at once.

• 56:34Lex Fridman?

  You'll solve nothing.

• 56:35Guido van Rossum?

  Uh, well, yeah, it's it's too overwhelming. And so I had a very, very focused problem. I wanted a programming language that sat somewhere in between shell scripting and C. And now arguably, there is like, one is higher level, one is lower level. And Python is sort of a language of an intermediate level, although it's still pretty much at the high level and.

• 57:16Lex Fridman?

  Nush.

• 57:16Guido van Rossum?

  I was, I was thinking about much more about.

• 57:22Guido van Rossum?

  I want a tool that I can use to be more productive as a programmer in a very specific environment. Uh, and I also had given myself a time budget for the development of the tool. And that was sort of about three months for both the design, like thinking through what are all the features of the language syntactically? Uh, and semantically, and how do I implement the whole pipeline from parsing the source code to executing it?

• 57:59Lex Fridman?

  So I think both with the timeline and the goals, it seems like productivity was at the core of it as a goal. So like for me, in the nineties and the first decade of the 21st century, I was always doing machine learning, AI. Programming for my research was always in C++. And then.

• 58:26Lex Fridman?

  And then the other people who are a little more mechanical engineering, electrical engineering are MATLAB-y. They're a little bit more MATLAB focused. Those are the world, and maybe a little bit of Java too. But people who are more interested in emphasizing the object-oriented nature of things. So, but then in the last 10 years or so, especially with the oncoming of neural networks and these packages that are built on Python to interface with neural networks, I switched to Python and it's just, I've noticed a significant boost that I can't exactly, because I don't think about it, but I can't exactly put into words why I'm just much, much more productive.

• 59:08Lex Fridman?

  Just being able to get the job done much, much faster. So, how do you think, whatever that qualitative difference is, I don't know if it's quantitative. It could be just a feeling. I don't know if I'm actually more productive, but how do you think about?

• 59:24Guido van Rossum?

  You probably are.

• 59:24Lex Fridman?

  Yeah, well, that's right. I think there's elements, let me just speak to one aspect that I think that was affecting my productivity is C++ was, I really enjoyed creating performant code and creating a beautiful structure where everything, you know, this kind of going into this, especially with the newer and newer standards of templated programming, of just really creating this beautiful formal structure that I found myself spending most of my time doing that as opposed to getting, parsing a file and extracting a few keywords or whatever the task I was trying to do. So, what is it about Python, how do you think of productivity in general as you were designing

• 1:00:08Lex Fridman?

  it now, sort of through the decades, last three decades? What do you think it means to be a productive programmer? And how did you try to design it into the language?

• 1:00:19Guido van Rossum?

  There are different tasks. And as a programmer, it's useful to have different tools available that sort of are suitable for different tasks. So, I still write C code, I still write shell code, but I write most of my things in Python.

• 1:00:41Guido van Rossum?

  Why do I still use those other languages? Because sometimes the task just demands it. And, well, I would say, most of the time, the task actually demands a certain language, because the task is not, "Write a program that solves problem X from scratch", but it's more like, "Fix a bug in existing program X", or "Add a small feature to an existing large program".

• 1:01:12Guido van Rossum?

  But, even if, if you sort of,

• 1:01:18Guido van Rossum?

  if you're not constrained in your choice of language by context like that,

• 1:01:26Guido van Rossum?

  there is still the fact that, if you write it in a certain language, then you sort of,

• 1:01:34Guido van Rossum?

  you, you have this balance between how long does it time, does it take you to write the code? And how long does the code run?

• 1:01:47Guido van Rossum?

  And, when you're in sort of, in the phase of exploring solutions, you often spend much more time writing the code than running it, because every time you've sort of, you've run it, you see that the output is not quite what you wanted, and you spend some more time coding.

• 1:02:14Guido van Rossum?

  And, a language like Python just makes that iteration much faster, because there are fewer details, there is a large library,

• 1:02:28Guido van Rossum?

  sort of, there are fewer details that, that you have to get right before your program compiles and runs. There are libraries that do all sorts of stuff for you, so you can sort of very quickly

• 1:02:42Guido van Rossum?

  Take a bunch of existing components, put them together and uh get your prototype application running, just like when I was building electronics, I was using a breadboard most of the time. So I I had this like sprawl out circuit that if you shook it, it would stop working because it was not put together very well, but it functioned and all I wanted was to see that it worked and then move on to the next next schematic or design or add something to it. Once you've sort of figured out, oh, this is the perfect design for my

• 1:03:25Guido van Rossum?

  radio or light sensor or whatever, then you can say, okay, how do we design a PCB for this? How do we solder the components in a small space? How do we make it so that it is robust against uh say voltage fluctuations uh or mechanical uh disruption? I mean, I know nothing about that when it comes to designing electronics, but I know a lot about that when it comes to to writing code.

• 1:03:56Lex Fridman?

  So the initial initial steps are uh efficient, fast, and there's not much stuff that gets in the way. But you're kind of describing um from a like Darwin described the evolution of species, right? You're you're observing of what is about true about Python. Now, if you take a step back, if the art of if the act of creating languages is art and you had three months to do it, initial steps, it so you just specified a bunch of goals, sort of things that you observe about Python, perhaps you had those goals, but how do you create the rules, the syntactic structure, the the features that result in

• 1:04:41Lex Fridman?

  those? So I have in the beginning, and I have follow up questions about through the evolution of Python too. But in the very beginning, when you're sitting there creating the the lexical analyzer, whatever.

• 1:04:53Guido van Rossum?

  Evolution was still a big part of it because.

• 1:04:58Guido van Rossum?

  I I sort of, I said to myself, I don't want to have to design everything from scratch. I'm going to borrow features from other languages that I like.

• 1:05:10Lex Fridman?

  Oh, interesting. So you basically, exactly. You first observe what you like.

• 1:05:14Guido van Rossum?

  Yeah, and so that's why if you're seventeen years old and you want to sort of create a programming language, you're not going to be very successful at it. Because you have no experience with other languages. Whereas I was in my,

• 1:05:33Guido van Rossum?

  let's say, mid thirties.

• 1:05:38Guido van Rossum?

  I had written parsers before, so I had worked on the implementation of ABC. I had spent years debating the design of ABC with its authors, with its designers. I had nothing to do with the design. It was designed fully as it ended up being implemented when I joined the team. But so, you borrow ideas and concepts and very concrete sort of local rules from different languages, like the indentation and certain other syntactic features from ABC. But I chose to borrow string literals and how numbers work from C and

• 1:06:22Guido van Rossum?

  various other things.

• 1:06:24Lex Fridman?

  So in then, if you take that further, so you had, you've had this funny sounding, but I think surprisingly accurate and at least practical title of Benevolent Dictator for Life for quite, you know, for the last three decades or whatever. Or no, not the actual title, but functionally speaking.

• 1:06:44Lex Fridman?

  So you had to make decisions, design decisions.

• 1:06:50Lex Fridman?

  Can you, maybe, uh, let's take Python 2, so Python, releasing Python 3 as an example.

• 1:06:58Lex Fridman?

  It's not backward compatible to Python 2 in, in ways that a lot of people know. So what was that deliberation, discussion, decision like? Yeah, what was the psychology of that experience? Do you regret any aspects of how that experience undergone?

• 1:07:15Guido van Rossum?

  Well, yeah, so it was a group process, really. It, it, at that point, even though I was BDFL in name, in name, and, and certainly, everybody sort of respected my, my position as the creator and, and the current sort of owner of the language design.

• 1:07:38Guido van Rossum?

  I was looking at everyone else for feedback. Sort of, Python 3.0, in some sense, was sparked by other people in the community,

• 1:07:51Guido van Rossum?

  pointing out, "Oh, well, there are a few issues that sort of bite users over and over. Can we do something about that?" And for Python 3, we took a number of those Python words, as they were called at the time. And we said, "Can we try to sort of make small changes to the language that address those words?" And we had sort of, in the past, we had always taken backwards compatibility very seriously.

• 1:08:31Guido van Rossum?

  And so many Python words in earlier versions had already been resolved because they could be resolved while maintaining backwards compatibility, or sort of using a very gradual path of evolution of the language in a certain area. And so we were stuck with a number of words that were widely recognized as problems, not like roadblocks, but nevertheless, sort of, things that some people trip over, and you know that.

• 1:09:03Guido van Rossum?

  That's always the same thing that that people trip over when they trip. And we could not think of a backwards compatible way of resolving those issues.

• 1:09:15Lex Fridman?

  But it's still an option to not resolve the issues.

• 1:09:17Guido van Rossum?

  And so, yes, for for a long time, we had sort of resigned ourselves to, well, okay, the language is not going to be perfect in this way and that way and that way. And we sort of, certainly of these, I mean, there are still plenty of things where you can say, well, that's, that particular detail is better in Java or in R or in Visual Basic or whatever.

• 1:09:48Guido van Rossum?

  And we're okay with that because, well, we can't easily change it.

• 1:09:54Guido van Rossum?

  It's not too bad. We can do a little bit with user education or we can have a static analyzer or warnings in in the parser or something. But there were things where we thought, well, these are really problems that are not going away. They are getting worse in the future. We should do something about.

• 1:10:18Lex Fridman?

  Should do something, but ultimately, there is a decision to be made, right?

• 1:10:21Guido van Rossum?

  Yes.

• 1:10:21Lex Fridman?

  So

• 1:10:24Lex Fridman?

  was that the toughest decision in the history of Python you had to make as the benevolent dictator for life? Or if not, what are there, maybe even on a smaller scale, what was the decision where you were really torn up about?

• 1:10:38Guido van Rossum?

  Well, the toughest decision was probably to resign.

• 1:10:43Lex Fridman?

  All right, let's go there. Hold on a second then. Let me just, because in the interest of time too, because I have a few cool questions for you. I mean, let's touch a really important one because it was quite dramatic and beautiful in certain kinds of ways. In July this year, three months ago, you wrote, now that PEP 572 is done, I don't ever want to have to fight so hard for a PEP and find that so many people despise my decisions. I would like to remove myself entirely from the decision process. I'll still be there for a while as an ordinary core developer and I'll still be available to mentor people, possibly more available.

• 1:11:21Lex Fridman?

  But I'm basically giving myself a permanent vacation from being BDFL, benevolent dictator for life. And you all will be on your own. First of all, it's almost Shakespearean. I'm not going to appoint a successor. So what are you all going to do? Create a democracy, anarchy, a dictatorship, a federation? So that was a very dramatic and beautiful

• 1:11:49Lex Fridman?

  set of statements. It's almost, it's open-ended nature. Called the community to create a future for Python. There's this kind of beautiful aspect to it.

• 1:11:58Guido van Rossum?

  Wow.

• 1:11:59Lex Fridman?

  So what, and dramatic, you know? What was making that decision like? What was on your heart, on your mind, stepping back now, a few months later?

• 1:12:10Lex Fridman?

  Take me through your mind.

• 1:12:11Guido van Rossum?

  I'm glad you liked the writing because it was actually written pretty quickly.

• 1:12:19Guido van Rossum?

  It was literally something like,

• 1:12:23Guido van Rossum?

  after months and months of

• 1:12:27Guido van Rossum?

  going around in circles, I had finally approved PEP 572, which I had a big hand in its design, although I didn't initiate

• 1:12:42Guido van Rossum?

  it originally. I sort of gave it a bunch of nudges in a direction that would be better for the language.

• 1:12:51Lex Fridman?

  So sorry, just to ask, is async I O is that's the one or no?

• 1:12:56Guido van Rossum?

  No, PEP 572 was actually a small feature, which is assignment expressions.

• 1:13:03Lex Fridman?

  Oh, assignment expressions, okay.

• 1:13:05Guido van Rossum?

  That had been,

• 1:13:08Guido van Rossum?

  there was just a lot of debate where a lot of people claimed that. They knew what was Pythonic and what was not Pythonic. And they knew that this was going to destroy the language. This was like a violation of Python's most fundamental design philosophy. And I thought that was all bullshit because I was in favor of it. And I would think I know something about Python's design philosophy. So I was really tired and also stressed of that thing. And literally after sort of announcing I was going to accept it.

• 1:13:46Guido van Rossum?

  A certain Wednesday evening, I had finally sent the email. It's accepted. Now let's just go implement it.

• 1:13:55Guido van Rossum?

  So I went to bed feeling really relieved. That's behind me. And I wake up Thursday morning, 7:00 AM. And I think, well, that was the last one.

• 1:14:10Guido van Rossum?

  That's going to be such, such a terrible debate. And that's going to be so. That's the last time that I let myself be so stressed out about a PEP decision. I should just resign. I've been sort of thinking about retirement for half a decade. I've been joking and sort of mentioning retirement. Sort of telling the community, some point in the future, I'm going to retire. Don't take that FL part of my title too literally. And I thought, okay, this is it. I'm done. I had the day off. I wanted to have a good time with my wife.

• 1:14:54Guido van Rossum?

  We were going to a little beach town nearby. And in, I think, maybe 15, 20 minutes, I wrote that thing that you just called Shakespearean. And the funny thing is.

• 1:15:08Lex Fridman?

  I'm gonna get so much crap for calling you Shakespearean.

• 1:15:10Guido van Rossum?

  I didn't even, I didn't even realize what a monumental decision it was. Because five minutes later, I read that link to my message back on Twitter. Where people were already discussing on Twitter, Guido resigned as the BDFL.

• 1:15:31Guido van Rossum?

  And I had, I had posted it on an internal forum that I thought was only read by core developers. So I thought I would at least have one day before the news would sort of get out.

• 1:15:44Lex Fridman?

  The on your own aspect had also an element of quite.

• 1:15:50Lex Fridman?

  It was quite a powerful element of the uncertainty that lies ahead. But can you also just briefly talk about, you know, like, for example, I play guitar. It's a hobby for fun. And whenever I play, people are super positive. It's super friendly. They're like, this is awesome. This is great. But sometimes I enter as an outside observer, I enter the programming community. And there seems to some, sometimes be camps on whatever the topic. And, and the two camps, the two or plus camps are often pretty harsh at criticizing the opposing camps.

• 1:16:27Lex Fridman?

  As an onlooker, I may be totally wrong on this.

• 1:16:30Guido van Rossum?

  Yeah, holy wars are, are sort of a favorite activity in the programming community.

• 1:16:36Lex Fridman?

  And what is the psychology behind that? Is, is that okay for a healthy community to have? Is that, is that a productive force ultimately for the evolution of a language?

• 1:16:45Guido van Rossum?

  Well, if everybody is patting each other on the back and never telling the truth.

• 1:16:52Lex Fridman?

  Yes.

• 1:16:55Guido van Rossum?

  It would not be a good thing. I think there is a middle ground where sort of.

• 1:17:04Guido van Rossum?

  Being nasty to each other is not okay. But there, there is, is, is a middle ground where there is healthy, ongoing criticism and feedback that is very productive. And you, you mean, at, at every level you see that. I mean, someone proposes to fix a very small issue in a codebase.

• 1:17:32Guido van Rossum?

  Chances are that some reviewer will sort of respond by saying, well, actually you can do it better the other way.

• 1:17:40Lex Fridman?

  Right.

• 1:17:43Guido van Rossum?

  When it comes to deciding on the future of the Python core developer community. We now have, I think, five or six competing proposals for a constitution.

• 1:17:57Lex Fridman?

  So that future, do you have a fear of that future? Do you have a hope for that future?

• 1:18:04Guido van Rossum?

  I'm very confident about that future. It by and large, I think that the debate has been very healthy and productive. Uh, and I actually, when, when I wrote that resignation email, I knew that, that Python was in a very good spot and that the Python core development community, the, the group of 50 or a hundred people who sort of write or review most of the code that goes into Python, those people get along very well, most of the time. Uh, a large number of different areas of expertise are represented.

• 1:18:52Guido van Rossum?

  Different levels of experience in the Python core dev community, different levels of experience completely outside it in software development in general, large systems, small systems, embedded systems. So I, I felt okay resigning because I knew that, that the community can really take care of itself.

• 1:19:19Lex Fridman?

  And out of a grab bag of future feature developments, let me ask if you can comment, maybe on all very quickly. Concurrent programming, parallel computing, async I O.

• 1:19:35Lex Fridman?

  These are things that people have, uh, expressed hope, complained about, whatever, have discussed on, on Reddit. Async I O, so the parallelization in general, uh, packaging. I, I was totally clueless on this. I just use pip to install stuff, but apparently there's pip and poetry. There's these dependency packaging systems that manage dependencies and so on. They're emerging and there's a lot of confusion about what's, what's the right thing to use. Then also, uh, functional programming, the, the ever.

• 1:20:07Lex Fridman?

  You know, are we going to get more functional programming or not? This kind of, this kind of idea. And of course, the, the GIL is a, connected to the parallelization, I suppose. The global interpreter lock problem. Can you just comment on whichever you want to comment on?

• 1:20:29Guido van Rossum?

  Well, let's take the GIL and parallelization and async I O as one, one topic.

• 1:20:41Guido van Rossum?

  I'm not that hopeful that Python will develop into a sort of high concurrency, high parallelism language. That's sort of the, the way the language is designed, the way most users use the language, the way the language is implemented, all make that a pretty unlikely future.

• 1:21:06Lex Fridman?

  So you, you think it might not even need to? Really, the way people use it, it, it might not be something that should be of great concern.

• 1:21:13Guido van Rossum?

  I think, I think async I O is a special case because it sort of allows overlapping I O and only I O. And that is, is a sort of best practice of supporting very high throughput I O, many connections per second.

• 1:21:37Guido van Rossum?

  I'm not worried about that. I think async I O will evolve. There are a couple of competing packages. We have some very smart people who are sort of pushing us in sort of to make async I O better. Parallel computing, I think that Python is not the language for that. There are, there are ways to work around it, but you sort of, you can't expect to write.

• 1:22:07Guido van Rossum?

  An algorithm in Python and have a compiler automatically parallelize that. What you can do is use a package like NumPy and there are a bunch of other very powerful packages that sort of use all the CPUs available because you tell the package, here's the data, here's the abstract operation to apply over it, go at it, and then we're back in the C++ world. But those packages are themselves implemented usually in C++.

• 1:22:39Lex Fridman?

  That's right. That's where TensorFlow and all these packages come in, where they parallelize across GPUs, for example. They take care of that for you. So in terms of packaging, can you comment on the future of packaging in Python?

• 1:22:51Guido van Rossum?

  Yeah, packaging has always been my least favorite topic. It's a really tough problem because the OS and the platform want to own packaging.

• 1:23:11Guido van Rossum?

  But their packaging solution is not specific to a language. Like if you take Linux, there are two competing packaging solutions for Linux or for Unix in general. But they all work across all languages. And several languages like Node, JavaScript, and Ruby, and Python all have their own packaging solutions that only work within the ecosystem of that language. Well, what should you use? That is a tough problem. My own approach is I use the system

• 1:23:55Guido van Rossum?

  packaging system to install Python and I use the Python packaging system then to install third-party Python packages. That's what most people do. Ten years ago, Python packaging was really a terrible situation. Nowadays, pip is the future. There is a separate ecosystem for numerical and scientific Python based on Anaconda. Those two can live together. I don't think there is a need for more than that.

• 1:24:29Lex Fridman?

  Great.

• 1:24:29Guido van Rossum?

  So that's packaging.

• 1:24:30Lex Fridman?

  That's, well, at least for me, that's where I've been extremely happy. I didn't even know this was an issue until it was brought up. Well, in the interest of time, let me sort of skip through a million other questions I have. So I watched the five hour, five and a half hour oral history that you've done with the Computer History Museum. And the nice thing about it, it gave this, because of the linear progression of the interview, it gave this feeling of a life, you know, a life well-lived with interesting things in it. Sort of a pretty, I would say, a good spend of this little existence we have on Earth.

• 1:25:09Lex Fridman?

  So outside of your family, looking back, what about this journey are you really proud of?

• 1:25:19Lex Fridman?

  Are there moments that stand out, accomplishments, ideas? Is it the creation of Python itself that stands out as a thing that you look back and say, damn, I did pretty good there?

• 1:25:33Guido van Rossum?

  Well, I would say that Python is definitely the best thing I've ever done. And I wouldn't sort of say just the creation of Python, but the way I sort of raised Python like a baby. I didn't just conceive a child, but I raised a child. And now I'm setting the child free in the world. And I've set up the child to sort of be able to take care of himself. And I'm very proud of that.

• 1:26:08Lex Fridman?

  And as the announcer of Monty Python's Flying Circus used to say, and now for something completely different, do you have a favorite Monty Python moment or a moment in Hitchhiker's Guide or any other literature, show, movie that cracks you up when you think about it?

• 1:26:23Guido van Rossum?

  Oh, you can always play me the parrot, the dead parrot sketch.

• 1:26:27Lex Fridman?

  Oh, that's brilliant.

• 1:26:28Guido van Rossum?

  Yeah.

• 1:26:29Lex Fridman?

  That's my favorite as well.

• 1:26:30Guido van Rossum?

  Pushing up the daisies.

• 1:26:33Lex Fridman?

  Okay, Greta, thank you so much for talking to me today.

• 1:26:37Guido van Rossum?

  Lex, it's been a great conversation.