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WEBVTT

00:00.000 --> 00:05.680
 The following is a conversation with Guido van Rossum, creator of Python, one of the most popular

00:05.680 --> 00:11.120
 programming languages in the world, used in almost any application that involves computers

00:11.120 --> 00:17.760
 from web back end development to psychology, neuroscience, computer vision, robotics, deep

00:17.760 --> 00:24.560
 learning, natural language processing, and almost any subfield of AI. This conversation is part of

00:24.560 --> 00:29.280
 MIT course on artificial general intelligence and the artificial intelligence podcast.

00:29.280 --> 00:36.080
 If you enjoy it, subscribe on YouTube, iTunes, or your podcast provider of choice, or simply connect

00:36.080 --> 00:44.720
 with me on Twitter at Lex Friedman, spelled F R I D. And now, here's my conversation with Guido van

00:44.720 --> 00:53.120
 Rossum. You were born in the Netherlands in 1956. Your parents and the world around you was deeply

00:53.120 --> 01:00.080
 deeply impacted by World War Two, as was my family from the Soviet Union. So with that context,

01:02.000 --> 01:07.360
 what is your view of human nature? Are some humans inherently good,

01:07.360 --> 01:12.240
 and some inherently evil? Or do we all have both good and evil within us?

01:12.240 --> 01:23.920
 Guido van Rossum Ouch, I did not expect such a deep one. I, I guess we all have good and evil

01:24.880 --> 01:31.440
 potential in us. And a lot of it depends on circumstances and context.

01:31.440 --> 01:38.800
 Peter Bell out of that world, at least on the Soviet Union side in Europe, sort of out of

01:38.800 --> 01:46.480
 suffering, out of challenge, out of that kind of set of traumatic events, often emerges beautiful

01:46.480 --> 01:53.200
 art, music, literature. In an interview I read or heard, you said you enjoyed Dutch literature

01:54.320 --> 01:59.760
 when you were a child. Can you tell me about the books that had an influence on you in your

01:59.760 --> 02:01.520
 childhood? Guido van Rossum

02:01.520 --> 02:09.120
 Well, with as a teenager, my favorite writer was my favorite Dutch author was a guy named Willem

02:09.120 --> 02:19.440
 Frederik Hermans, who's writing, certainly his early novels were all about sort of

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 ambiguous things that happened during World War Two. I think he was a young adult during that time.

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 And he wrote about it a lot, and very interesting, very good books, I thought, I think.

02:40.800 --> 02:42.560
 Peter Bell In a nonfiction way?

02:42.560 --> 02:46.400
 Guido van Rossum No, it was all fiction, but it was

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 very much set in the ambiguous world of resistance against the Germans,

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 where often you couldn't tell whether someone was truly in the resistance or really a spy for the

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 Germans. And some of the characters in his novels sort of crossed that line, and you never really

03:11.280 --> 03:13.840
 find out what exactly happened.

03:13.840 --> 03:16.880
 Peter Bell And in his novels, there's always a

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 good guy and a bad guy, the nature of good and evil. Is it clear there's a hero?

03:22.160 --> 03:25.120
 Guido van Rossum No, his heroes are often more,

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 his main characters are often anti heroes. And so they're not very heroic. They're often,

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 they fail at some level to accomplish their lofty goals.

03:40.800 --> 03:43.040
 Peter Bell And looking at the trajectory

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

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 outside the technical world that you existed in?

03:54.160 --> 03:59.920
 Guido van Rossum I still read novels.

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

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 Peter Bell It doesn't impact your work.

04:07.280 --> 04:10.080
 Guido van Rossum It's a separate world.

04:10.080 --> 04:17.440
 My work is highly technical and sort of the world of art and literature doesn't really

04:17.440 --> 04:19.120
 directly have any bearing on it.

04:19.120 --> 04:22.400
 Peter Bell You don't think there's a creative element

04:22.400 --> 04:26.880
 to the design? You know, some would say design of a language is art.

04:26.880 --> 04:32.160
 Guido van Rossum I'm not disagreeing with that.

04:32.160 --> 04:39.360
 I'm just saying that sort of I don't feel direct influences from more traditional art

04:39.360 --> 04:40.880
 on my own creativity.

04:40.880 --> 04:43.280
 Peter Bell Right. Of course, you don't feel doesn't mean

04:43.280 --> 04:46.000
 it's not somehow deeply there in your subconscious.

04:46.000 --> 04:48.240
 Guido van Rossum Who knows?

04:48.240 --> 04:51.200
 Peter Bell Who knows? So let's go back to your early

04:51.200 --> 04:57.440
 teens. Your hobbies were building electronic circuits, building mechanical models.

04:57.440 --> 05:06.080
 What if you can just put yourself back in the mind of that young Guido 12, 13, 14, was

05:06.080 --> 05:12.240
 that grounded in a desire to create a system? So to create something? Or was it more just

05:12.240 --> 05:14.720
 tinkering? Just the joy of puzzle solving?

05:14.720 --> 05:18.720
 Guido van Rossum I think it was more the latter, actually.

05:18.720 --> 05:29.920
 I maybe towards the end of my high school period, I felt confident enough that that

05:29.920 --> 05:39.120
 I designed my own circuits that were sort of interesting somewhat. But a lot of that

05:39.120 --> 05:46.000
 time, I literally just took a model kit and follow the instructions, putting the things

05:46.000 --> 05:51.680
 together. I mean, I think the first few years that I built electronics kits, I really did

05:51.680 --> 05:59.760
 not have enough understanding of sort of electronics to really understand what I was doing. I mean,

05:59.760 --> 06:06.480
 I could debug it, and I could sort of follow the instructions very carefully, which has

06:06.480 --> 06:14.560
 always stayed with me. But I had a very naive model of, like, how do I build a circuit?

06:14.560 --> 06:22.800
 Of, like, how a transistor works? And I don't think that in those days, I had any understanding

06:22.800 --> 06:32.560
 of coils and capacitors, which actually sort of was a major problem when I started to build

06:32.560 --> 06:39.840
 more complex digital circuits, because I was unaware of the sort of the analog part of

06:39.840 --> 06:50.080
 the – how they actually work. And I would have things that – the schematic looked

06:50.080 --> 06:57.440everything looked fine, and it didn't work. And what I didn't realize was that

06:57.440 --> 07:02.720
 there was some megahertz level oscillation that was throwing the circuit off, because

07:02.720 --> 07:13.360
 I had a sort of – two wires were too close, or the switches were kind of poorly built.

07:13.360 --> 07:19.280
 But through that time, I think it's really interesting and instructive to think about,

07:19.280 --> 07:24.600
 because echoes of it are in this time now. So in the 1970s, the personal computer was

07:24.600 --> 07:33.200
 being born. So did you sense, in tinkering with these circuits, did you sense the encroaching

07:33.200 --> 07:39.320
 revolution in personal computing? So if at that point, we would sit you down and ask

07:39.320 --> 07:46.040
 you to predict the 80s and the 90s, do you think you would be able to do so successfully

07:46.040 --> 07:55.560
 to unroll the process that's happening? No, I had no clue. I remember, I think, in

07:55.560 --> 08:03.060
 the summer after my senior year – or maybe it was the summer after my junior year – well,

08:03.060 --> 08:11.600
 at some point, I think, when I was 18, I went on a trip to the Math Olympiad in Eastern

08:11.600 --> 08:16.920
 Europe, and there was like – I was part of the Dutch team, and there were other nerdy

08:16.920 --> 08:23.040
 kids that sort of had different experiences, and one of them told me about this amazing

08:23.040 --> 08:31.840
 thing called a computer. And I had never heard that word. My own explorations in electronics

08:31.840 --> 08:40.420
 were sort of about very simple digital circuits, and I had sort of – I had the idea that

08:40.420 --> 08:49.760
 I somewhat understood how a digital calculator worked. And so there is maybe some echoes

08:49.760 --> 08:56.440
 of computers there, but I never made that connection. I didn't know that when my parents

08:56.440 --> 09:03.520
 were paying for magazine subscriptions using punched cards, that there was something called

09:03.520 --> 09:08.260
 a computer that was involved that read those cards and transferred the money between accounts.

09:08.260 --> 09:15.880
 I was also not really interested in those things. It was only when I went to university

09:15.880 --> 09:23.120
 to study math that I found out that they had a computer, and students were allowed to use

09:23.120 --> 09:24.120
 it.

09:24.120 --> 09:27.800
 And there were some – you're supposed to talk to that computer by programming it.

09:27.800 --> 09:29.920
 What did that feel like, finding –

09:29.920 --> 09:35.440
 Yeah, that was the only thing you could do with it. The computer wasn't really connected

09:35.440 --> 09:41.400
 to the real world. The only thing you could do was sort of – you typed your program

09:41.400 --> 09:47.840
 on a bunch of punched cards. You gave the punched cards to the operator, and an hour

09:47.840 --> 09:55.520
 later the operator gave you back your printout. And so all you could do was write a program

09:55.520 --> 10:04.080
 that did something very abstract. And I don't even remember what my first forays into programming

10:04.080 --> 10:13.440
 were, but they were sort of doing simple math exercises and just to learn how a programming

10:13.440 --> 10:15.560
 language worked.

10:15.560 --> 10:21.680
 Did you sense, okay, first year of college, you see this computer, you're able to have

10:21.680 --> 10:29.420
 a program and it generates some output. Did you start seeing the possibility of this,

10:29.420 --> 10:34.920
 or was it a continuation of the tinkering with circuits? Did you start to imagine that

10:34.920 --> 10:42.460
 one, the personal computer, but did you see it as something that is a tool, like a word

10:42.460 --> 10:47.160
 processing tool, maybe for gaming or something? Or did you start to imagine that it could

10:47.160 --> 10:53.860
 be going to the world of robotics, like the Frankenstein picture that you could create

10:53.860 --> 10:59.640
 an artificial being? There's like another entity in front of you. You did not see the

10:59.640 --> 11:00.640
 computer.

11:00.640 --> 11:05.840
 I don't think I really saw it that way. I was really more interested in the tinkering.

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 It's maybe not a sort of a complete coincidence that I ended up sort of creating a programming

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 language which is a tool for other programmers. I've always been very focused on the sort

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 of activity of programming itself and not so much what happens with the program you

11:28.920 --> 11:29.920
 write.

11:29.920 --> 11:30.920
 Right.

11:30.920 --> 11:37.800
 I do remember, and I don't remember, maybe in my second or third year, probably my second

11:37.800 --> 11:46.680
 actually, someone pointed out to me that there was this thing called Conway's Game of Life.

11:46.680 --> 11:50.480
 You're probably familiar with it. I think –

11:50.480 --> 11:53.200
 In the 70s, I think is when they came up with it.

11:53.200 --> 12:00.840
 So there was a Scientific American column by someone who did a monthly column about

12:00.840 --> 12:06.580
 mathematical diversions. I'm also blanking out on the guy's name. It was very famous

12:06.580 --> 12:12.440
 at the time and I think up to the 90s or so. And one of his columns was about Conway's

12:12.440 --> 12:18.160
 Game of Life and he had some illustrations and he wrote down all the rules and sort of

12:18.160 --> 12:23.720
 there was the suggestion that this was philosophically interesting, that that was why Conway had

12:23.720 --> 12:31.480
 called it that. And all I had was like the two pages photocopy of that article. I don't

12:31.480 --> 12:40.200
 even remember where I got it. But it spoke to me and I remember implementing a version

12:40.200 --> 12:49.000
 of that game for the batch computer we were using where I had a whole Pascal program that

12:49.000 --> 12:56.480
 sort of read an initial situation from input and read some numbers that said do so many

12:56.480 --> 13:05.960
 generations and print every so many generations and then out would come pages and pages of

13:05.960 --> 13:08.480
 sort of things.

13:08.480 --> 13:18.360
 I remember much later I've done a similar thing using Python but that original version

13:18.360 --> 13:27.700
 I wrote at the time I found interesting because I combined it with some trick I had learned

13:27.700 --> 13:36.000
 during my electronics hobbyist times. I essentially first on paper I designed a simple circuit

13:36.000 --> 13:45.780
 built out of logic gates that took nine bits of input which is sort of the cell and its

13:45.780 --> 13:54.040
 neighbors and produced a new value for that cell and it's like a combination of a half

13:54.040 --> 14:01.040
 adder and some other clipping. It's actually a full adder. And so I had worked that out

14:01.040 --> 14:10.520
 and then I translated that into a series of Boolean operations on Pascal integers where

14:10.520 --> 14:21.740
 you could use the integers as bitwise values. And so I could basically generate 60 bits

14:21.740 --> 14:28.800
 of a generation in like eight instructions or so.

14:28.800 --> 14:29.800
 Nice.

14:29.800 --> 14:32.560
 So I was proud of that.

14:32.560 --> 14:38.120
 It's funny that you mentioned, so for people who don't know Conway's Game of Life, it's

14:38.120 --> 14:44.840
 a cellular automata where there's single compute units that kind of look at their neighbors

14:44.840 --> 14:50.080
 and figure out what they look like in the next generation based on the state of their

14:50.080 --> 14:57.840
 neighbors and this is deeply distributed system in concept at least. And then there's simple

14:57.840 --> 15:04.400
 rules that all of them follow and somehow out of this simple rule when you step back

15:04.400 --> 15:13.160
 and look at what occurs, it's beautiful. There's an emergent complexity. Even though the underlying

15:13.160 --> 15:17.440
 rules are simple, there's an emergent complexity. Now the funny thing is you've implemented

15:17.440 --> 15:23.660
 this and the thing you're commenting on is you're proud of a hack you did to make it

15:23.660 --> 15:30.800
 run efficiently. When you're not commenting on, it's a beautiful implementation, you're

15:30.800 --> 15:36.780
 not commenting on the fact that there's an emergent complexity that you've coded a simple

15:36.780 --> 15:42.960
 program and when you step back and you print out the following generation after generation,

15:42.960 --> 15:48.400
 that's stuff that you may have not predicted would happen is happening.

15:48.400 --> 15:53.600
 And is that magic? I mean, that's the magic that all of us feel when we program. When

15:53.600 --> 15:59.240
 you create a program and then you run it and whether it's Hello World or it shows something

15:59.240 --> 16:03.840
 on screen, if there's a graphical component, are you seeing the magic in the mechanism

16:03.840 --> 16:05.200
 of creating that?

16:05.200 --> 16:14.440
 I think I went back and forth. As a student, we had an incredibly small budget of computer

16:14.440 --> 16:20.280
 time that we could use. It was actually measured. I once got in trouble with one of my professors

16:20.280 --> 16:29.640
 because I had overspent the department's budget. It's a different story.

16:29.640 --> 16:36.900
 I actually wanted the efficient implementation because I also wanted to explore what would

16:36.900 --> 16:48.560
 happen with a larger number of generations and a larger size of the board. Once the implementation

16:48.560 --> 16:57.000
 was flawless, I would feed it different patterns and then I think maybe there was a follow

16:57.000 --> 17:03.620
 up article where there were patterns that were like gliders, patterns that repeated

17:03.620 --> 17:13.200
 themselves after a number of generations but translated one or two positions to the right

17:13.200 --> 17:21.720
 or up or something like that. I remember things like glider guns. Well, you can Google Conway's

17:21.720 --> 17:27.560
 Game of Life. People still go aww and ooh over it.

17:27.560 --> 17:32.680
 For a reason because it's not really well understood why. I mean, this is what Stephen

17:32.680 --> 17:40.240
 Wolfram is obsessed about. We don't have the mathematical tools to describe the kind of

17:40.240 --> 17:45.120
 complexity that emerges in these kinds of systems. The only way you can do is to run

17:45.120 --> 17:47.120
 it.

17:47.120 --> 17:55.720
 I'm not convinced that it's sort of a problem that lends itself to classic mathematical

17:55.720 --> 17:59.920
 analysis.

17:59.920 --> 18:05.120
 One theory of how you create an artificial intelligence or artificial being is you kind

18:05.120 --> 18:10.120
 of have to, same with the Game of Life, you kind of have to create a universe and let

18:10.120 --> 18:17.520
 it run. That creating it from scratch in a design way, coding up a Python program that

18:17.520 --> 18:22.760
 creates a fully intelligent system may be quite challenging. You might need to create

18:22.760 --> 18:27.120
 a universe just like the Game of Life.

18:27.120 --> 18:33.200
 You might have to experiment with a lot of different universes before there is a set

18:33.200 --> 18:41.480
 of rules that doesn't essentially always just end up repeating itself in a trivial

18:41.480 --> 18:42.480
 way.

18:42.480 --> 18:49.840
 Yeah, and Stephen Wolfram works with these simple rules, says that it's kind of surprising

18:49.840 --> 18:55.280
 how quickly you find rules that create interesting things. You shouldn't be able to, but somehow

18:55.280 --> 19:02.120
 you do. And so maybe our universe is laden with rules that will create interesting things

19:02.120 --> 19:07.440
 that might not look like humans, but emergent phenomena that's interesting may not be as

19:07.440 --> 19:09.440
 difficult to create as we think.

19:09.440 --> 19:10.440
 Sure.

19:10.440 --> 19:17.440
 But let me sort of ask, at that time, some of the world, at least in popular press, was

19:17.440 --> 19:25.680
 kind of captivated, perhaps at least in America, by the idea of artificial intelligence, that

19:25.680 --> 19:33.240
 these computers would be able to think pretty soon. And did that touch you at all? In science

19:33.240 --> 19:37.800
 fiction or in reality in any way?

19:37.800 --> 19:49.000
 I didn't really start reading science fiction until much, much later. I think as a teenager

19:49.000 --> 19:54.520
 I read maybe one bundle of science fiction stories.

19:54.520 --> 19:57.960
 Was it in the background somewhere, like in your thoughts?

19:57.960 --> 20:04.720
 That sort of the using computers to build something intelligent always felt to me, because

20:04.720 --> 20:12.920
 I felt I had so much understanding of what actually goes on inside a computer. I knew

20:12.920 --> 20:22.880
 how many bits of memory it had and how difficult it was to program. And sort of, I didn't believe

20:22.880 --> 20:30.560
 at all that you could just build something intelligent out of that, that would really

20:30.560 --> 20:40.600
 sort of satisfy my definition of intelligence. I think the most influential thing that I

20:40.600 --> 20:48.680
 read in my early twenties was Gödel Escherbach. That was about consciousness, and that was

20:48.680 --> 20:54.040
 a big eye opener in some sense.

20:54.040 --> 21:00.760
 In what sense? So, on your own brain, did you at the time or do you now see your own

21:00.760 --> 21:07.720
 brain as a computer? Or is there a total separation of the way? So yeah, you're very pragmatically

21:07.720 --> 21:14.600
 practically know the limits of memory, the limits of this sequential computing or weakly

21:14.600 --> 21:21.000
 paralyzed computing, and you just know what we have now, and it's hard to see how it creates.

21:21.000 --> 21:29.920
 But it's also easy to see, it was in the 40s, 50s, 60s, and now at least similarities between

21:29.920 --> 21:31.680
 the brain and our computers.

21:31.680 --> 21:43.200
 Oh yeah, I mean, I totally believe that brains are computers in some sense. I mean, the rules

21:43.200 --> 21:51.200
 they use to play by are pretty different from the rules we can sort of implement in our

21:51.200 --> 22:02.960
 current hardware, but I don't believe in, like, a separate thing that infuses us with

22:02.960 --> 22:10.480
 intelligence or consciousness or any of that. There's no soul, I've been an atheist

22:10.480 --> 22:18.800
 probably from when I was 10 years old, just by thinking a bit about math and the universe,

22:18.800 --> 22:26.640
 and well, my parents were atheists. Now, I know that you could be an atheist and still

22:26.640 --> 22:34.080
 believe that there is something sort of about intelligence or consciousness that cannot

22:34.080 --> 22:44.560
 possibly emerge from a fixed set of rules. I am not in that camp. I totally see that,

22:44.560 --> 22:53.680
 sort of, given how many millions of years evolution took its time, DNA is a particular

22:53.680 --> 23:07.040
 machine that sort of encodes information and an unlimited amount of information in chemical

23:07.040 --> 23:12.320
 form and has figured out a way to replicate itself.

23:12.320 --> 23:16.880
 I thought that that was, maybe it's 300 million years ago, but I thought it was closer

23:16.880 --> 23:25.120
 to half a billion years ago, that that's sort of originated and it hasn't really changed,

23:25.120 --> 23:32.040
 that the sort of the structure of DNA hasn't changed ever since. That is like our binary

23:32.040 --> 23:35.200
 code that we have in hardware. I mean...

23:35.200 --> 23:39.760
 The basic programming language hasn't changed, but maybe the programming itself...

23:39.760 --> 23:48.320
 Obviously, it did sort of, it happened to be a set of rules that was good enough to

23:48.320 --> 23:59.520
 sort of develop endless variability and sort of the idea of self replicating molecules

23:59.520 --> 24:05.360
 competing with each other for resources and one type eventually sort of always taking

24:05.360 --> 24:12.320
 over. That happened before there were any fossils, so we don't know how that exactly

24:12.320 --> 24:17.920
 happened, but I believe it's clear that that did happen.

24:17.920 --> 24:25.360
 Can you comment on consciousness and how you see it? Because I think we'll talk about

24:25.360 --> 24:30.080
 programming quite a bit. We'll talk about, you know, intelligence connecting to programming

24:30.080 --> 24:38.080
 fundamentally, but consciousness is this whole other thing. Do you think about it often as

24:38.080 --> 24:45.440
 a developer of a programming language and as a human?

24:45.440 --> 24:55.000
 Those are pretty sort of separate topics. Sort of my line of work working with programming

24:55.000 --> 25:02.720
 does not involve anything that goes in the direction of developing intelligence or consciousness,

25:02.720 --> 25:13.880
 but sort of privately as an avid reader of popular science writing, I have some thoughts

25:13.880 --> 25:25.680
 which is mostly that I don't actually believe that consciousness is an all or nothing thing.

25:25.680 --> 25:35.960
 I have a feeling that, and I forget what I read that influenced this, but I feel that

25:35.960 --> 25:41.400
 if you look at a cat or a dog or a mouse, they have some form of intelligence. If you

25:41.400 --> 25:54.040
 look at a fish, it has some form of intelligence, and that evolution just took a long time,

25:54.040 --> 26:01.320
 but I feel that the sort of evolution of more and more intelligence that led to sort of

26:01.320 --> 26:12.920
 the human form of intelligence followed the evolution of the senses, especially the visual

26:12.920 --> 26:20.480
 sense. I mean, there is an enormous amount of processing that's needed to interpret

26:20.480 --> 26:28.240
 a scene, and humans are still better at that than computers are.

26:28.240 --> 26:39.660
 And I have a feeling that there is a sort of, the reason that like mammals in particular

26:39.660 --> 26:47.960
 developed the levels of consciousness that they have and that eventually sort of going

26:47.960 --> 26:55.360
 from intelligence to self awareness and consciousness has to do with sort of being a robot that

26:55.360 --> 26:58.920
 has very highly developed senses.

26:58.920 --> 27:04.760
 Has a lot of rich sensory information coming in, so that's a really interesting thought

27:04.760 --> 27:14.200
 that whatever that basic mechanism of DNA, whatever that basic building blocks of programming,

27:14.200 --> 27:21.080
 if you just add more abilities, more high resolution sensors, more sensors, you just

27:21.080 --> 27:26.760
 keep stacking those things on top that this basic programming in trying to survive develops

27:26.760 --> 27:35.000
 very interesting things that start to us humans to appear like intelligence and consciousness.

27:35.000 --> 27:42.280
 As far as robots go, I think that the self driving cars have that sort of the greatest

27:42.280 --> 27:50.400
 opportunity of developing something like that, because when I drive myself, I don't just

27:50.400 --> 27:53.800
 pay attention to the rules of the road.

27:53.800 --> 28:01.220
 I also look around and I get clues from that, oh, this is a shopping district, oh, here's

28:01.220 --> 28:08.960
 an old lady crossing the street, oh, here is someone carrying a pile of mail, there's

28:08.960 --> 28:14.040
 a mailbox, I bet you they're going to cross the street to reach that mailbox.

28:14.040 --> 28:17.520
 And I slow down, and I don't even think about that.

28:17.520 --> 28:25.780
 And so, there is so much where you turn your observations into an understanding of what

28:25.780 --> 28:32.680
 other consciousnesses are going to do, or what other systems in the world are going

28:32.680 --> 28:37.400
 to be, oh, that tree is going to fall.

28:37.400 --> 28:46.800
 I see sort of, I see much more of, I expect somehow that if anything is going to become

28:46.800 --> 28:55.520
 unconscious, it's going to be the self driving car and not the network of a bazillion computers

28:55.520 --> 29:03.160
 in a Google or Amazon data center that are all networked together to do whatever they

29:03.160 --> 29:04.160
 do.

29:04.160 --> 29:09.640
 So, in that sense, so you actually highlight, because that's what I work in Thomas Vehicles,

29:09.640 --> 29:15.600
 you highlight the big gap between what we currently can't do and what we truly need

29:15.600 --> 29:18.500
 to be able to do to solve the problem.

29:18.500 --> 29:24.600
 Under that formulation, then consciousness and intelligence is something that basically

29:24.600 --> 29:30.020
 a system should have in order to interact with us humans, as opposed to some kind of

29:30.020 --> 29:35.280
 abstract notion of a consciousness.

29:35.280 --> 29:39.200
 Consciousness is something that you need to have to be able to empathize, to be able to

29:39.200 --> 29:47.440
 fear, understand what the fear of death is, all these aspects that are important for interacting

29:47.440 --> 29:56.160
 with pedestrians, you need to be able to do basic computation based on our human desires

29:56.160 --> 29:57.160
 and thoughts.

29:57.160 --> 30:02.280
 And if you sort of, yeah, if you look at the dog, the dog clearly knows, I mean, I'm

30:02.280 --> 30:07.340
 not the dog owner, but I have friends who have dogs, the dogs clearly know what the

30:07.340 --> 30:11.400
 humans around them are going to do, or at least they have a model of what those humans

30:11.400 --> 30:14.160
 are going to do and they learn.

30:14.160 --> 30:19.060
 Some dogs know when you're going out and they want to go out with you, they're sad when

30:19.060 --> 30:26.080
 you leave them alone, they cry, they're afraid because they were mistreated when they were

30:26.080 --> 30:31.040
 younger.

30:31.040 --> 30:39.280
 We don't assign sort of consciousness to dogs, or at least not all that much, but I also

30:39.280 --> 30:42.500
 don't think they have none of that.

30:42.500 --> 30:50.360
 So I think it's consciousness and intelligence are not all or nothing.

30:50.360 --> 30:52.780
 The spectrum is really interesting.

30:52.780 --> 30:58.760
 But in returning to programming languages and the way we think about building these

30:58.760 --> 31:03.260
 kinds of things, about building intelligence, building consciousness, building artificial

31:03.260 --> 31:04.260
 beings.

31:04.260 --> 31:10.920
 So I think one of the exciting ideas came in the 17th century and with Leibniz, Hobbes,

31:10.920 --> 31:18.520
 Descartes, where there's this feeling that you can convert all thought, all reasoning,

31:18.520 --> 31:24.480
 all the thing that we find very special in our brains, you can convert all of that into

31:24.480 --> 31:25.480
 logic.

31:25.480 --> 31:30.400
 So you can formalize it, formal reasoning, and then once you formalize everything, all

31:30.400 --> 31:34.400
 of knowledge, then you can just calculate and that's what we're doing with our brains

31:34.400 --> 31:35.400
 is we're calculating.

31:35.400 --> 31:40.240
 So there's this whole idea that this is possible, that this we can actually program.

31:40.240 --> 31:46.520
 But they weren't aware of the concept of pattern matching in the sense that we are aware of

31:46.520 --> 31:47.640
 it now.

31:47.640 --> 31:57.640
 They sort of thought they had discovered incredible bits of mathematics like Newton's calculus

31:57.640 --> 32:06.840
 and their sort of idealism, their sort of extension of what they could do with logic

32:06.840 --> 32:18.000
 and math sort of went along those lines and they thought there's like, yeah, logic.

32:18.000 --> 32:22.020
 There's like a bunch of rules and a bunch of input.

32:22.020 --> 32:28.600
 They didn't realize that how you recognize a face is not just a bunch of rules but is

32:28.600 --> 32:39.160
 a shit ton of data plus a circuit that sort of interprets the visual clues and the context

32:39.160 --> 32:49.400
 and everything else and somehow can massively parallel pattern match against stored rules.

32:49.400 --> 32:56.320
 I mean, if I see you tomorrow here in front of the Dropbox office, I might recognize you.

32:56.320 --> 33:01.320
 Even if I'm wearing a different shirt, yeah, but if I see you tomorrow in a coffee shop

33:01.320 --> 33:06.640
 in Belmont, I might have no idea that it was you or on the beach or whatever.

33:06.640 --> 33:10.160
 I make those kind of mistakes myself all the time.

33:10.160 --> 33:16.320
 I see someone that I only know as like, oh, this person is a colleague of my wife's and

33:16.320 --> 33:20.860
 then I see them at the movies and I didn't recognize them.

33:20.860 --> 33:29.320
 But do you see those, you call it pattern matching, do you see that rules is unable

33:29.320 --> 33:32.380
 to encode that?

33:32.380 --> 33:36.320
 Everything you see, all the pieces of information you look around this room, I'm wearing a black

33:36.320 --> 33:41.720
 shirt, I have a certain height, I'm a human, all these, there's probably tens of thousands

33:41.720 --> 33:45.680
 of facts you pick up moment by moment about this scene.

33:45.680 --> 33:50.000
 You take them for granted and you aggregate them together to understand the scene.

33:50.000 --> 33:53.800
 You don't think all of that could be encoded to where at the end of the day, you can just

33:53.800 --> 33:57.440
 put it all on the table and calculate?

33:57.440 --> 33:58.840
 I don't know what that means.

33:58.840 --> 34:08.680
 I mean, yes, in the sense that there is no actual magic there, but there are enough layers

34:08.680 --> 34:17.640
 of abstraction from the facts as they enter my eyes and my ears to the understanding of

34:17.640 --> 34:29.240
 the scene that I don't think that AI has really covered enough of that distance.

34:29.240 --> 34:37.800
 It's like if you take a human body and you realize it's built out of atoms, well, that

34:37.800 --> 34:41.960
 is a uselessly reductionist view, right?

34:41.960 --> 34:46.380
 The body is built out of organs, the organs are built out of cells, the cells are built

34:46.380 --> 34:53.240
 out of proteins, the proteins are built out of amino acids, the amino acids are built

34:53.240 --> 34:58.040
 out of atoms and then you get to quantum mechanics.

34:58.040 --> 34:59.920
 So that's a very pragmatic view.

34:59.920 --> 35:03.720
 I mean, obviously as an engineer, I agree with that kind of view, but you also have

35:03.720 --> 35:13.160
 to consider the Sam Harris view of, well, intelligence is just information processing.

35:13.160 --> 35:17.320
 Like you said, you take in sensory information, you do some stuff with it and you come up

35:17.320 --> 35:20.760
 with actions that are intelligent.

35:20.760 --> 35:22.480
 That makes it sound so easy.

35:22.480 --> 35:24.280
 I don't know who Sam Harris is.

35:24.280 --> 35:26.400
 Oh, well, it's a philosopher.

35:26.400 --> 35:29.680
 So like this is how philosophers often think, right?

35:29.680 --> 35:33.760
 And essentially that's what Descartes was, is wait a minute, if there is, like you said,

35:33.760 --> 35:39.320
 no magic, so he basically says it doesn't appear like there's any magic, but we know

35:39.320 --> 35:44.280
 so little about it that it might as well be magic.

35:44.280 --> 35:47.800
 So just because we know that we're made of atoms, just because we know we're made

35:47.800 --> 35:53.280
 of organs, the fact that we know very little how to get from the atoms to organs in a way

35:53.280 --> 36:00.400
 that's recreatable means that you shouldn't get too excited just yet about the fact that

36:00.400 --> 36:02.240
 you figured out that we're made of atoms.

36:02.240 --> 36:11.920
 Right, and the same about taking facts as our sensory organs take them in and turning

36:11.920 --> 36:19.820
 that into reasons and actions, that sort of, there are a lot of abstractions that we haven't

36:19.820 --> 36:23.960
 quite figured out how to deal with those.

36:23.960 --> 36:37.440
 I mean, sometimes, I don't know if I can go on a tangent or not, so if I take a simple

36:37.440 --> 36:45.640
 program that parses, say I have a compiler that parses a program, in a sense the input

36:45.640 --> 36:55.640
 routine of that compiler, of that parser, is a sensing organ, and it builds up a mighty

36:55.640 --> 37:01.960
 complicated internal representation of the program it just saw, it doesn't just have

37:01.960 --> 37:08.200
 a linear sequence of bytes representing the text of the program anymore, it has an abstract

37:08.200 --> 37:15.480
 syntax tree, and I don't know how many of your viewers or listeners are familiar with

37:15.480 --> 37:18.680
 compiler technology, but there's…

37:18.680 --> 37:21.880
 Fewer and fewer these days, right?

37:21.880 --> 37:24.920
 That's also true, probably.

37:24.920 --> 37:30.360
 People want to take a shortcut, but there's sort of, this abstraction is a data structure

37:30.360 --> 37:37.480
 that the compiler then uses to produce outputs that is relevant, like a translation of that

37:37.480 --> 37:47.880
 program to machine code that can be executed by hardware, and then that data structure

37:47.880 --> 37:50.600
 gets thrown away.

37:50.600 --> 38:02.560
 When a fish or a fly sees, sort of gets visual impulses, I'm sure it also builds up some

38:02.560 --> 38:10.000
 data structure, and for the fly that may be very minimal, a fly may have only a few, I

38:10.000 --> 38:17.680
 mean, in the case of a fly's brain, I could imagine that there are few enough layers of

38:17.680 --> 38:24.040
 abstraction that it's not much more than when it's darker here than it is here, well

38:24.040 --> 38:29.880
 it can sense motion, because a fly sort of responds when you move your arm towards it,

38:29.880 --> 38:39.240
 so clearly its visual processing is intelligent, well, not intelligent, but it has an abstraction

38:39.240 --> 38:46.440
 for motion, and we still have similar things in, but much more complicated in our brains,

38:46.440 --> 38:50.400
 I mean, otherwise you couldn't drive a car if you couldn't, if you didn't have an

38:50.400 --> 38:53.480
 incredibly good abstraction for motion.

38:53.480 --> 38:59.160
 Yeah, in some sense, the same abstraction for motion is probably one of the primary

38:59.160 --> 39:05.080
 sources of our, of information for us, we just know what to do, I think we know what

39:05.080 --> 39:08.280
 to do with that, we've built up other abstractions on top.

39:08.280 --> 39:14.120
 We build much more complicated data structures based on that, and we build more persistent

39:14.120 --> 39:20.320
 data structures, sort of after some processing, some information sort of gets stored in our

39:20.320 --> 39:27.240
 memory pretty much permanently, and is available on recall, I mean, there are some things that

39:27.240 --> 39:34.040
 you sort of, you're conscious that you're remembering it, like, you give me your phone

39:34.040 --> 39:39.560
 number, I, well, at my age I have to write it down, but I could imagine, I could remember

39:39.560 --> 39:46.240
 those seven numbers, or ten digits, and reproduce them in a while, if I sort of repeat them

39:46.240 --> 39:53.320
 to myself a few times, so that's a fairly conscious form of memorization.

39:53.320 --> 39:57.800
 On the other hand, how do I recognize your face, I have no idea.

39:57.800 --> 40:04.080
 My brain has a whole bunch of specialized hardware that knows how to recognize faces,

40:04.080 --> 40:10.200
 I don't know how much of that is sort of coded in our DNA, and how much of that is

40:10.200 --> 40:17.960
 trained over and over between the ages of zero and three, but somehow our brains know

40:17.960 --> 40:26.000
 how to do lots of things like that, that are useful in our interactions with other humans,

40:26.000 --> 40:29.880
 without really being conscious of how it's done anymore.

40:29.880 --> 40:36.200
 Right, so our actual day to day lives, we're operating at the very highest level of abstraction,

40:36.200 --> 40:39.760
 we're just not even conscious of all the little details underlying it.

40:39.760 --> 40:43.360
 There's compilers on top of, it's like turtles on top of turtles, or turtles all the way

40:43.360 --> 40:48.200
 down, there's compilers all the way down, but that's essentially, you say that there's

40:48.200 --> 40:54.920
 no magic, that's what I, what I was trying to get at, I think, is with Descartes started

40:54.920 --> 40:59.600
 this whole train of saying that there's no magic, I mean, there's all this beforehand.

40:59.600 --> 41:06.120
 Well didn't Descartes also have the notion though that the soul and the body were fundamentally

41:06.120 --> 41:07.120
 separate?

41:07.120 --> 41:11.800
 Separate, yeah, I think he had to write in God in there for political reasons, so I don't

41:11.800 --> 41:17.880
 know actually, I'm not a historian, but there's notions in there that all of reasoning, all

41:17.880 --> 41:20.120
 of human thought can be formalized.

41:20.120 --> 41:28.480
 I think that continued in the 20th century with Russell and with Gadot's incompleteness

41:28.480 --> 41:33.120
 theorem, this debate of what are the limits of the things that could be formalized, that's

41:33.120 --> 41:37.960
 where the Turing machine came along, and this exciting idea, I mean, underlying a lot of

41:37.960 --> 41:43.160
 computing that you can do quite a lot with a computer.

41:43.160 --> 41:47.640
 You can encode a lot of the stuff we're talking about in terms of recognizing faces and so

41:47.640 --> 41:53.960
 on, theoretically, in an algorithm that can then run on a computer.

41:53.960 --> 42:05.040
 And in that context, I'd like to ask programming in a philosophical way, what does it mean

42:05.040 --> 42:06.480
 to program a computer?

42:06.480 --> 42:13.360
 So you said you write a Python program or compiled a C++ program that compiles to some

42:13.360 --> 42:21.200
 byte code, it's forming layers, you're programming a layer of abstraction that's higher, how

42:21.200 --> 42:24.920
 do you see programming in that context?

42:24.920 --> 42:29.800
 Can it keep getting higher and higher levels of abstraction?

42:29.800 --> 42:35.960
 I think at some point the higher levels of abstraction will not be called programming

42:35.960 --> 42:44.720
 and they will not resemble what we call programming at the moment.

42:44.720 --> 42:52.080
 There will not be source code, I mean, there will still be source code sort of at a lower

42:52.080 --> 42:59.320
 level of the machine, just like there are still molecules and electrons and sort of

42:59.320 --> 43:09.120
 proteins in our brains, but, and so there's still programming and system administration

43:09.120 --> 43:15.960
 and who knows what, to keep the machine running, but what the machine does is a different level

43:15.960 --> 43:23.060
 of abstraction in a sense, and as far as I understand the way that for the last decade

43:23.060 --> 43:28.440
 or more people have made progress with things like facial recognition or the self driving

43:28.440 --> 43:38.200
 cars is all by endless, endless amounts of training data where at least as a lay person,

43:38.200 --> 43:47.420
 and I feel myself totally as a lay person in that field, it looks like the researchers

43:47.420 --> 43:57.400
 who publish the results don't necessarily know exactly how their algorithms work, and

43:57.400 --> 44:04.840
 I often get upset when I sort of read a sort of a fluff piece about Facebook in the newspaper

44:04.840 --> 44:12.680
 or social networks and they say, well, algorithms, and that's like a totally different interpretation

44:12.680 --> 44:19.240
 of the word algorithm, because for me, the way I was trained or what I learned when I

44:19.240 --> 44:25.920
 was eight or ten years old, an algorithm is a set of rules that you completely understand

44:25.920 --> 44:30.720
 that can be mathematically analyzed and you can prove things.

44:30.720 --> 44:37.840
 You can like prove that Aristotelian sieve produces all prime numbers and only prime

44:37.840 --> 44:38.840
 numbers.

44:38.840 --> 44:39.840
 Yeah.

44:39.840 --> 44:44.360
 So I don't know if you know who Andrej Karpathy is, I'm afraid not.

44:44.360 --> 44:51.980
 So he's a head of AI at Tesla now, but he was at Stanford before and he has this cheeky

44:51.980 --> 44:56.480
 way of calling this concept software 2.0.

44:56.480 --> 45:00.120
 So let me disentangle that for a second.

45:00.120 --> 45:06.080
 So kind of what you're referring to is the traditional, the algorithm, the concept of

45:06.080 --> 45:09.560
 an algorithm, something that's there, it's clear, you can read it, you understand it,

45:09.560 --> 45:14.800
 you can prove it's functioning as kind of software 1.0.

45:14.800 --> 45:21.920
 And what software 2.0 is, is exactly what you described, which is you have neural networks,

45:21.920 --> 45:26.600
 which is a type of machine learning that you feed a bunch of data and that neural network

45:26.600 --> 45:30.200
 learns to do a function.

45:30.200 --> 45:35.220
 All you specify is the inputs and the outputs you want and you can't look inside.

45:35.220 --> 45:37.040
 You can't analyze it.

45:37.040 --> 45:41.920
 All you can do is train this function to map the inputs to the outputs by giving a lot

45:41.920 --> 45:42.920
 of data.

45:42.920 --> 45:47.040
 And that's as programming becomes getting a lot of data.

45:47.040 --> 45:48.920
 That's what programming is.

45:48.920 --> 45:52.120
 Well, that would be programming 2.0.

45:52.120 --> 45:53.800
 To programming 2.0.

45:53.800 --> 45:55.600
 I wouldn't call that programming.

45:55.600 --> 45:57.480
 It's just a different activity.

45:57.480 --> 46:02.640
 Just like building organs out of cells is not called chemistry.

46:02.640 --> 46:09.680
 Well, so let's just step back and think sort of more generally, of course.

46:09.680 --> 46:18.080
 But you know, it's like as a parent teaching your kids, things can be called programming.

46:18.080 --> 46:22.720
 In that same sense, that's how programming is being used.

46:22.720 --> 46:27.080
 You're providing them data, examples, use cases.

46:27.080 --> 46:36.680
 So imagine writing a function not by, not with for loops and clearly readable text,

46:36.680 --> 46:42.760
 but more saying, well, here's a lot of examples of what this function should take.

46:42.760 --> 46:47.860
 And here's a lot of examples of when it takes those functions, it should do this.

46:47.860 --> 46:50.280
 And then figure out the rest.

46:50.280 --> 46:52.640
 So that's the 2.0 concept.

46:52.640 --> 46:58.560
 And so the question I have for you is like, it's a very fuzzy way.

46:58.560 --> 47:01.680
 This is the reality of a lot of these pattern recognition systems and so on.

47:01.680 --> 47:05.400
 It's a fuzzy way of quote unquote programming.

47:05.400 --> 47:09.160
 What do you think about this kind of world?

47:09.160 --> 47:13.640
 Should it be called something totally different than programming?

47:13.640 --> 47:21.000
 If you're a software engineer, does that mean you're designing systems that are very, can

47:21.000 --> 47:28.140
 be systematically tested, evaluated, they have a very specific specification and then this

47:28.140 --> 47:33.520
 other fuzzy software 2.0 world, machine learning world, that's something else totally?

47:33.520 --> 47:41.000
 Or is there some intermixing that's possible?

47:41.000 --> 47:48.600
 Well the question is probably only being asked because we don't quite know what that software

47:48.600 --> 47:51.400
 2.0 actually is.

47:51.400 --> 48:02.960
 And I think there is a truism that every task that AI has tackled in the past, at some point

48:02.960 --> 48:09.160
 we realized how it was done and then it was no longer considered part of artificial intelligence

48:09.160 --> 48:15.200
 because it was no longer necessary to use that term.

48:15.200 --> 48:21.600
 It was just, oh now we know how to do this.

48:21.600 --> 48:30.320
 And a new field of science or engineering has been developed and I don't know if sort

48:30.320 --> 48:39.000
 of every form of learning or sort of controlling computer systems should always be called programming.

48:39.000 --> 48:43.720
 So I don't know, maybe I'm focused too much on the terminology.

48:43.720 --> 48:56.200
 But I expect that there just will be different concepts where people with sort of different

48:56.200 --> 49:07.920
 education and a different model of what they're trying to do will develop those concepts.

49:07.920 --> 49:17.240
 I guess if you could comment on another way to put this concept is, I think the kind of

49:17.240 --> 49:23.480
 functions that neural networks provide is things as opposed to being able to upfront

49:23.480 --> 49:28.720
 prove that this should work for all cases you throw at it.

49:28.720 --> 49:32.320
 All you're able, it's the worst case analysis versus average case analysis.

49:32.320 --> 49:39.800
 All you're able to say is it seems on everything we've tested to work 99.9% of the time, but

49:39.800 --> 49:44.160
 we can't guarantee it and it fails in unexpected ways.

49:44.160 --> 49:48.080
 We can't even give you examples of how it fails in unexpected ways, but it's like really

49:48.080 --> 49:50.120
 good most of the time.

49:50.120 --> 50:00.720
 Is there no room for that in current ways we think about programming?

50:00.720 --> 50:11.080
 programming 1.0 is actually sort of getting to that point too, where the sort of the ideal

50:11.080 --> 50:21.120
 of a bug free program has been abandoned long ago by most software developers.

50:21.120 --> 50:30.120
 We only care about bugs that manifest themselves often enough to be annoying.

50:30.120 --> 50:40.680
 And we're willing to take the occasional crash or outage or incorrect result for granted

50:40.680 --> 50:47.600
 because we can't possibly, we don't have enough programmers to make all the code bug free

50:47.600 --> 50:50.200
 and it would be an incredibly tedious business.

50:50.200 --> 50:56.320
 And if you try to throw formal methods at it, it becomes even more tedious.

50:56.320 --> 51:05.520
 So every once in a while the user clicks on a link and somehow they get an error and the

51:05.520 --> 51:07.360
 average user doesn't panic.

51:07.360 --> 51:14.840
 They just click again and see if it works better the second time, which often magically

51:14.840 --> 51:21.600
 it does, or they go up and they try some other way of performing their tasks.

51:21.600 --> 51:29.880
 So that's sort of an end to end recovery mechanism and inside systems there is all

51:29.880 --> 51:39.120
 sorts of retries and timeouts and fallbacks and I imagine that that sort of biological

51:39.120 --> 51:46.320
 systems are even more full of that because otherwise they wouldn't survive.

51:46.320 --> 51:54.160
 Do you think programming should be taught and thought of as exactly what you just said?

51:54.160 --> 52:01.560
 I come from this kind of, you're always denying that fact always.

52:01.560 --> 52:12.680
 In sort of basic programming education, the sort of the programs you're having students

52:12.680 --> 52:23.480
 write are so small and simple that if there is a bug you can always find it and fix it.

52:23.480 --> 52:29.720
 Because the sort of programming as it's being taught in some, even elementary, middle schools,

52:29.720 --> 52:36.680
 in high school, introduction to programming classes in college typically, it's programming

52:36.680 --> 52:38.920
 in the small.

52:38.920 --> 52:47.560
 Very few classes sort of actually teach software engineering, building large systems.

52:47.560 --> 52:51.360
 Every summer here at Dropbox we have a large number of interns.

52:51.360 --> 52:56.720
 Every tech company on the West Coast has the same thing.

52:56.720 --> 53:02.520
 These interns are always amazed because this is the first time in their life that they

53:02.520 --> 53:12.920
 see what goes on in a really large software development environment.

53:12.920 --> 53:20.280
 Everything they've learned in college was almost always about a much smaller scale and

53:20.280 --> 53:27.840
 somehow that difference in scale makes a qualitative difference in how you do things and how you

53:27.840 --> 53:29.600
 think about it.

53:29.600 --> 53:36.300
 If you then take a few steps back into decades, 70s and 80s, when you were first thinking

53:36.300 --> 53:41.840
 about Python or just that world of programming languages, did you ever think that there would

53:41.840 --> 53:46.720
 be systems as large as underlying Google, Facebook, and Dropbox?

53:46.720 --> 53:51.440
 Did you, when you were thinking about Python?

53:51.440 --> 53:57.520
 I was actually always caught by surprise by sort of this, yeah, pretty much every stage

53:57.520 --> 53:59.680
 of computing.

53:59.680 --> 54:07.280
 So maybe just because you've spoken in other interviews, but I think the evolution of programming

54:07.280 --> 54:13.080
 languages are fascinating and it's especially because it leads from my perspective towards

54:13.080 --> 54:15.640
 greater and greater degrees of intelligence.

54:15.640 --> 54:21.880
 I learned the first programming language I played with in Russia was with the Turtle

54:21.880 --> 54:22.880
 logo.

54:22.880 --> 54:24.840
 Logo, yeah.

54:24.840 --> 54:29.960
 And if you look, I just have a list of programming languages, all of which I've now played with

54:29.960 --> 54:30.960
 a little bit.

54:30.960 --> 54:36.640
 I mean, they're all beautiful in different ways from Fortran, Cobalt, Lisp, Algol 60,

54:36.640 --> 54:46.160
 Basic, Logo again, C, as a few, the object oriented came along in the 60s, Simula, Pascal,

54:46.160 --> 54:47.560
 Smalltalk.

54:47.560 --> 54:48.560
 All of that leads.

54:48.560 --> 54:49.560
 They're all the classics.

54:49.560 --> 54:50.560
 The classics.

54:50.560 --> 54:51.560
 Yeah.

54:51.560 --> 54:52.560
 The classic hits, right?

54:52.560 --> 54:58.280
 Steam, that's built on top of Lisp.

54:58.280 --> 55:05.900
 On the database side, SQL, C++, and all of that leads up to Python, Pascal too, and that's

55:05.900 --> 55:10.960
 before Python, MATLAB, these kind of different communities, different languages.

55:10.960 --> 55:13.240
 So can you talk about that world?

55:13.240 --> 55:18.680
 I know that sort of Python came out of ABC, which I actually never knew that language.

55:18.680 --> 55:24.400
 I just, having researched this conversation, went back to ABC and it looks remarkably,

55:24.400 --> 55:31.240
 it has a lot of annoying qualities, but underneath those, like all caps and so on, but underneath

55:31.240 --> 55:35.720
 that, there's elements of Python that are quite, they're already there.

55:35.720 --> 55:37.540
 That's where I got all the good stuff.

55:37.540 --> 55:38.540
 All the good stuff.

55:38.540 --> 55:41.580
 So, but in that world, you're swimming these programming languages, were you focused on

55:41.580 --> 55:48.080
 just the good stuff in your specific circle, or did you have a sense of what is everyone

55:48.080 --> 55:49.080
 chasing?

55:49.080 --> 55:57.000
 You said that every programming language is built to scratch an itch.

55:57.000 --> 55:59.920
 Were you aware of all the itches in the community?

55:59.920 --> 56:05.080
 And if not, or if yes, I mean, what itch were you trying to scratch with Python?

56:05.080 --> 56:12.040
 Well, I'm glad I wasn't aware of all the itches because I would probably not have been able

56:12.040 --> 56:14.040
 to do anything.

56:14.040 --> 56:19.760
 I mean, if you're trying to solve every problem at once, you'll solve nothing.

56:19.760 --> 56:23.880
 Well, yeah, it's too overwhelming.

56:23.880 --> 56:28.360
 And so I had a very, very focused problem.

56:28.360 --> 56:41.880
 I wanted a programming language that sat somewhere in between shell scripting and C. And now,

56:41.880 --> 56:48.720
 arguably, there is like, one is higher level, one is lower level.

56:48.720 --> 56:56.760
 And Python is sort of a language of an intermediate level, although it's still pretty much at

56:56.760 --> 57:00.560
 the high level end.

57:00.560 --> 57:11.200
 I was thinking about much more about, I want a tool that I can use to be more productive

57:11.200 --> 57:16.640
 as a programmer in a very specific environment.

57:16.640 --> 57:22.280
 And I also had given myself a time budget for the development of the tool.

57:22.280 --> 57:29.340
 And that was sort of about three months for both the design, like thinking through what

57:29.340 --> 57:38.900
 are all the features of the language syntactically and semantically, and how do I implement the

57:38.900 --> 57:43.680
 whole pipeline from parsing the source code to executing it.

57:43.680 --> 57:51.440
 So I think both with the timeline and the goals, it seems like productivity was at the

57:51.440 --> 57:54.040
 core of it as a goal.

57:54.040 --> 58:01.280
 So like, for me in the 90s, and the first decade of the 21st century, I was always doing

58:01.280 --> 58:07.620
 machine learning, AI programming for my research was always in C++.

58:07.620 --> 58:14.240
 And then the other people who are a little more mechanical engineering, electrical engineering,

58:14.240 --> 58:15.240
 are MATLABby.

58:15.240 --> 58:18.520
 They're a little bit more MATLAB focused.

58:18.520 --> 58:21.200
 Those are the world, and maybe a little bit Java too.

58:21.200 --> 58:29.160
 But people who are more interested in emphasizing the object oriented nature of things.

58:29.160 --> 58:34.920
 So within the last 10 years or so, especially with the oncoming of neural networks and these

58:34.920 --> 58:41.360
 packages that are built on Python to interface with neural networks, I switched to Python

58:41.360 --> 58:47.120
 and it's just, I've noticed a significant boost that I can't exactly, because I don't

58:47.120 --> 58:52.840
 think about it, but I can't exactly put into words why I'm just much, much more productive.

58:52.840 --> 58:56.400
 Just being able to get the job done much, much faster.

58:56.400 --> 59:01.880
 So how do you think, whatever that qualitative difference is, I don't know if it's quantitative,

59:01.880 --> 59:07.280
 it could be just a feeling, I don't know if I'm actually more productive, but how

59:07.280 --> 59:08.280
 do you think about...

59:08.280 --> 59:09.280
 You probably are.

59:09.280 --> 59:10.280
 Yeah.

59:10.280 --> 59:11.880
 Well, that's right.

59:11.880 --> 59:15.400
 I think there's elements, let me just speak to one aspect that I think that was affecting

59:15.400 --> 59:26.160
 my productivity is C++ was, I really enjoyed creating performant code and creating a beautiful

59:26.160 --> 59:31.000
 structure where everything that, you know, this kind of going into this, especially with

59:31.000 --> 59:37.080
 the newer and newer standards of templated programming of just really creating this beautiful

59:37.080 --> 59:42.000
 formal structure that I found myself spending most of my time doing that as opposed to getting

59:42.000 --> 59:47.520
 it, parsing a file and extracting a few keywords or whatever the task was trying to do.

59:47.520 --> 59:49.980
 So what is it about Python?

59:49.980 --> 59:54.520
 How do you think of productivity in general as you were designing it now, sort of through

59:54.520 --> 1:00:00.120
 the decades, last three decades, what do you think it means to be a productive programmer?

1:00:00.120 --> 1:00:03.560
 And how did you try to design it into the language?

1:00:03.560 --> 1:00:10.400
 There are different tasks and as a programmer, it's useful to have different tools available

1:00:10.400 --> 1:00:13.940
 that sort of are suitable for different tasks.

1:00:13.940 --> 1:00:25.600
 So I still write C code, I still write shell code, but I write most of my things in Python.

1:00:25.600 --> 1:00:33.000
 Why do I still use those other languages, because sometimes the task just demands it.

1:00:33.000 --> 1:00:39.000
 And well, I would say most of the time the task actually demands a certain language because

1:00:39.000 --> 1:00:45.600
 the task is not write a program that solves problem X from scratch, but it's more like

1:00:45.600 --> 1:00:56.680
 fix a bug in existing program X or add a small feature to an existing large program.

1:00:56.680 --> 1:01:10.160
 But even if you're not constrained in your choice of language by context like that, there

1:01:10.160 --> 1:01:21.360
 is still the fact that if you write it in a certain language, then you have this balance

1:01:21.360 --> 1:01:31.840
 between how long does it take you to write the code and how long does the code run?

1:01:31.840 --> 1:01:42.760
 And when you're in the phase of exploring solutions, you often spend much more time

1:01:42.760 --> 1:01:50.720
 writing the code than running it because every time you've run it, you see that the output

1:01:50.720 --> 1:01:58.480
 is not quite what you wanted and you spend some more time coding.

1:01:58.480 --> 1:02:06.760
 And a language like Python just makes that iteration much faster because there are fewer

1:02:06.760 --> 1:02:19.480
 details that you have to get right before your program compiles and runs.

1:02:19.480 --> 1:02:26.400
 There are libraries that do all sorts of stuff for you, so you can sort of very quickly take

1:02:26.400 --> 1:02:36.320
 a bunch of existing components, put them together, and get your prototype application running.

1:02:36.320 --> 1:02:42.860
 Just like when I was building electronics, I was using a breadboard most of the time,

1:02:42.860 --> 1:02:51.320
 so I had this sprawl out circuit that if you shook it, it would stop working because it

1:02:51.320 --> 1:02:58.800
 was not put together very well, but it functioned and all I wanted was to see that it worked

1:02:58.800 --> 1:03:05.000
 and then move on to the next schematic or design or add something to it.

1:03:05.000 --> 1:03:10.500
 Once you've sort of figured out, oh, this is the perfect design for my radio or light

1:03:10.500 --> 1:03:15.800
 sensor or whatever, then you can say, okay, how do we design a PCB for this?

1:03:15.800 --> 1:03:19.920
 How do we solder the components in a small space?

1:03:19.920 --> 1:03:32.840
 How do we make it so that it is robust against, say, voltage fluctuations or mechanical disruption?

1:03:32.840 --> 1:03:37.320
 I know nothing about that when it comes to designing electronics, but I know a lot about

1:03:37.320 --> 1:03:40.400
 that when it comes to writing code.

1:03:40.400 --> 1:03:46.080
 So the initial steps are efficient, fast, and there's not much stuff that gets in the

1:03:46.080 --> 1:03:56.680
 way, but you're kind of describing, like Darwin described the evolution of species, right?

1:03:56.680 --> 1:04:00.520
 You're observing of what is true about Python.

1:04:00.520 --> 1:04:07.800
 Now if you take a step back, if the act of creating languages is art and you had three

1:04:07.800 --> 1:04:15.640
 months to do it, initial steps, so you just specified a bunch of goals, sort of things

1:04:15.640 --> 1:04:19.400
 that you observe about Python, perhaps you had those goals, but how do you create the

1:04:19.400 --> 1:04:25.600
 rules, the syntactic structure, the features that result in those?

1:04:25.600 --> 1:04:29.880
 So I have in the beginning and I have follow up questions about through the evolution of

1:04:29.880 --> 1:04:35.440
 Python too, but in the very beginning when you were sitting there creating the lexical

1:04:35.440 --> 1:04:37.440
 analyzer or whatever.

1:04:37.440 --> 1:04:47.240
 Python was still a big part of it because I sort of, I said to myself, I don't want

1:04:47.240 --> 1:04:53.640
 to have to design everything from scratch, I'm going to borrow features from other languages

1:04:53.640 --> 1:04:54.640
 that I like.

1:04:54.640 --> 1:04:55.640
 Oh, interesting.

1:04:55.640 --> 1:04:58.360
 So you basically, exactly, you first observe what you like.

1:04:58.360 --> 1:05:05.240
 Yeah, and so that's why if you're 17 years old and you want to sort of create a programming

1:05:05.240 --> 1:05:11.600
 language, you're not going to be very successful at it because you have no experience with

1:05:11.600 --> 1:05:24.300
 other languages, whereas I was in my, let's say mid 30s, I had written parsers before,

1:05:24.300 --> 1:05:30.880
 so I had worked on the implementation of ABC, I had spent years debating the design of ABC

1:05:30.880 --> 1:05:37.520
 with its authors, with its designers, I had nothing to do with the design, it was designed

1:05:37.520 --> 1:05:42.080
 fully as it ended up being implemented when I joined the team.

1:05:42.080 --> 1:05:51.440
 But so you borrow ideas and concepts and very concrete sort of local rules from different

1:05:51.440 --> 1:05:58.920
 languages like the indentation and certain other syntactic features from ABC, but I chose

1:05:58.920 --> 1:06:07.960
 to borrow string literals and how numbers work from C and various other things.

1:06:07.960 --> 1:06:13.800
 So in then, if you take that further, so yet you've had this funny sounding, but I think

1:06:13.800 --> 1:06:21.000
 surprisingly accurate and at least practical title of benevolent dictator for life for

1:06:21.000 --> 1:06:25.240
 quite, you know, for the last three decades or whatever, or no, not the actual title,

1:06:25.240 --> 1:06:27.940
 but functionally speaking.

1:06:27.940 --> 1:06:34.280
 So you had to make decisions, design decisions.

1:06:34.280 --> 1:06:41.960
 Can you maybe, let's take Python 2, so releasing Python 3 as an example.

1:06:41.960 --> 1:06:47.240
 It's not backward compatible to Python 2 in ways that a lot of people know.

1:06:47.240 --> 1:06:50.640
 So what was that deliberation, discussion, decision like?

1:06:50.640 --> 1:06:51.640
 Yeah.

1:06:51.640 --> 1:06:54.520
 What was the psychology of that experience?

1:06:54.520 --> 1:06:58.520
 Do you regret any aspects of how that experience undergone that?

1:06:58.520 --> 1:07:03.040
 Well, yeah, so it was a group process really.

1:07:03.040 --> 1:07:11.880
 At that point, even though I was BDFL in name and certainly everybody sort of respected

1:07:11.880 --> 1:07:22.160
 my position as the creator and the current sort of owner of the language design, I was

1:07:22.160 --> 1:07:26.560
 looking at everyone else for feedback.

1:07:26.560 --> 1:07:35.280
 Sort of Python 3.0 in some sense was sparked by other people in the community pointing

1:07:35.280 --> 1:07:46.360
 out, oh, well, there are a few issues that sort of bite users over and over.

1:07:46.360 --> 1:07:48.920
 Can we do something about that?

1:07:48.920 --> 1:07:56.360
 And for Python 3, we took a number of those Python words as they were called at the time

1:07:56.360 --> 1:08:04.800
 and we said, can we try to sort of make small changes to the language that address those

1:08:04.800 --> 1:08:06.560
 words?

1:08:06.560 --> 1:08:15.360
 And we had sort of in the past, we had always taken backwards compatibility very seriously.

1:08:15.360 --> 1:08:20.420
 And so many Python words in earlier versions had already been resolved because they could

1:08:20.420 --> 1:08:29.740
 be resolved while maintaining backwards compatibility or sort of using a very gradual path of evolution

1:08:29.740 --> 1:08:31.960
 of the language in a certain area.

1:08:31.960 --> 1:08:39.760
 And so we were stuck with a number of words that were widely recognized as problems, not

1:08:39.760 --> 1:08:47.680
 like roadblocks, but nevertheless sort of things that some people trip over and you know that

1:08:47.680 --> 1:08:52.080
 that's always the same thing that people trip over when they trip.

1:08:52.080 --> 1:08:58.480
 And we could not think of a backwards compatible way of resolving those issues.

1:08:58.480 --> 1:09:01.920
 But it's still an option to not resolve the issues, right?

1:09:01.920 --> 1:09:07.920
 And so yes, for a long time, we had sort of resigned ourselves to, well, okay, the language

1:09:07.920 --> 1:09:13.400
 is not going to be perfect in this way and that way and that way.

1:09:13.400 --> 1:09:19.440
 And we sort of, certain of these, I mean, there are still plenty of things where you

1:09:19.440 --> 1:09:32.680
 can say, well, that particular detail is better in Java or in R or in Visual Basic or whatever.

1:09:32.680 --> 1:09:37.960
 And we're okay with that because, well, we can't easily change it.

1:09:37.960 --> 1:09:38.960
 It's not too bad.

1:09:38.960 --> 1:09:47.180
 We can do a little bit with user education or we can have a static analyzer or warnings

1:09:47.180 --> 1:09:49.440
 in the parse or something.

1:09:49.440 --> 1:09:54.880
 But there were things where we thought, well, these are really problems that are not going

1:09:54.880 --> 1:09:55.880
 away.

1:09:55.880 --> 1:10:00.840
 They are getting worse in the future.

1:10:00.840 --> 1:10:03.040
 We should do something about that.

1:10:03.040 --> 1:10:05.640
 But ultimately there is a decision to be made, right?

1:10:05.640 --> 1:10:13.320
 So was that the toughest decision in the history of Python you had to make as the benevolent

1:10:13.320 --> 1:10:15.180
 dictator for life?

1:10:15.180 --> 1:10:20.160
 Or if not, what are there, maybe even on the smaller scale, what was the decision where

1:10:20.160 --> 1:10:22.040
 you were really torn up about?

1:10:22.040 --> 1:10:25.800
 Well, the toughest decision was probably to resign.

1:10:25.800 --> 1:10:28.120
 All right, let's go there.

1:10:28.120 --> 1:10:29.360
 Hold on a second then.

1:10:29.360 --> 1:10:33.200
 Let me just, because in the interest of time too, because I have a few cool questions for

1:10:33.200 --> 1:10:38.160
 you and let's touch a really important one because it was quite dramatic and beautiful

1:10:38.160 --> 1:10:40.400
 in certain kinds of ways.

1:10:40.400 --> 1:10:47.320
 In July this year, three months ago, you wrote, now that PEP 572 is done, I don't ever want

1:10:47.320 --> 1:10:52.680
 to have to fight so hard for a PEP and find that so many people despise my decisions.

1:10:52.680 --> 1:10:56.240
 I would like to remove myself entirely from the decision process.

1:10:56.240 --> 1:11:01.520
 I'll still be there for a while as an ordinary core developer and I'll still be available

1:11:01.520 --> 1:11:05.440
 to mentor people, possibly more available.

1:11:05.440 --> 1:11:11.000
 But I'm basically giving myself a permanent vacation from being BDFL, benevolent dictator

1:11:11.000 --> 1:11:12.000
 for life.

1:11:12.000 --> 1:11:14.240
 And you all will be on your own.

1:11:14.240 --> 1:11:19.720
 First of all, it's almost Shakespearean.

1:11:19.720 --> 1:11:22.300
 I'm not going to appoint a successor.

1:11:22.300 --> 1:11:24.640
 So what are you all going to do?

1:11:24.640 --> 1:11:29.240
 Create a democracy, anarchy, a dictatorship, a federation?

1:11:29.240 --> 1:11:34.560
 So that was a very dramatic and beautiful set of statements.

1:11:34.560 --> 1:11:40.080
 It's almost, it's open ended nature called the community to create a future for Python.

1:11:40.080 --> 1:11:43.280
 It's just kind of a beautiful aspect to it.

1:11:43.280 --> 1:11:48.320
 So what, and dramatic, you know, what was making that decision like?

1:11:48.320 --> 1:11:54.560
 What was on your heart, on your mind, stepping back now a few months later?

1:11:54.560 --> 1:12:02.940
 I'm glad you liked the writing because it was actually written pretty quickly.

1:12:02.940 --> 1:12:14.240
 It was literally something like after months and months of going around in circles, I had

1:12:14.240 --> 1:12:26.240
 finally approved PEP572, which I had a big hand in its design, although I didn't initiate

1:12:26.240 --> 1:12:27.760
 it originally.

1:12:27.760 --> 1:12:36.320
 I sort of gave it a bunch of nudges in a direction that would be better for the language.

1:12:36.320 --> 1:12:40.320
 So sorry, just to ask, is async IO, that's the one or no?

1:12:40.320 --> 1:12:49.320
 PEP572 was actually a small feature, which is assignment expressions.

1:12:49.320 --> 1:12:58.200
 That had been, there was just a lot of debate where a lot of people claimed that they knew

1:12:58.200 --> 1:13:04.800
 what was Pythonic and what was not Pythonic, and they knew that this was going to destroy

1:13:04.800 --> 1:13:06.080
 the language.

1:13:06.080 --> 1:13:11.800
 This was like a violation of Python's most fundamental design philosophy, and I thought

1:13:11.800 --> 1:13:17.200
 that was all bullshit because I was in favor of it, and I would think I know something

1:13:17.200 --> 1:13:19.120
 about Python's design philosophy.

1:13:19.120 --> 1:13:26.340
 So I was really tired and also stressed of that thing, and literally after sort of announcing

1:13:26.340 --> 1:13:34.560
 I was going to accept it, a certain Wednesday evening I had finally sent the email, it's

1:13:34.560 --> 1:13:35.560
 accepted.

1:13:35.560 --> 1:13:38.920
 I can just go implement it.

1:13:38.920 --> 1:13:44.120
 So I went to bed feeling really relieved, that's behind me.

1:13:44.120 --> 1:13:54.320
 And I wake up Thursday morning, 7 a.m., and I think, well, that was the last one that's

1:13:54.320 --> 1:14:03.880
 going to be such a terrible debate, and that's the last time that I let myself be so stressed

1:14:03.880 --> 1:14:06.520
 out about a pep decision.

1:14:06.520 --> 1:14:07.920
 I should just resign.

1:14:07.920 --> 1:14:15.520
 I've been sort of thinking about retirement for half a decade, I've been joking and sort

1:14:15.520 --> 1:14:22.460
 of mentioning retirement, sort of telling the community at some point in the future

1:14:22.460 --> 1:14:29.400
 I'm going to retire, don't take that FL part of my title too literally.

1:14:29.400 --> 1:14:32.080
 And I thought, okay, this is it.

1:14:32.080 --> 1:14:39.200
 I'm done, I had the day off, I wanted to have a good time with my wife, we were going to

1:14:39.200 --> 1:14:48.480
 a little beach town nearby, and in I think maybe 15, 20 minutes I wrote that thing that

1:14:48.480 --> 1:14:51.320
 you just called Shakespearean.

1:14:51.320 --> 1:15:01.560
 The funny thing is I didn't even realize what a monumental decision it was, because

1:15:01.560 --> 1:15:09.200
 five minutes later I read that link to my message back on Twitter, where people were

1:15:09.200 --> 1:15:15.280
 already discussing on Twitter, Guido resigned as the BDFL.

1:15:15.280 --> 1:15:22.440
 And I had posted it on an internal forum that I thought was only read by core developers,

1:15:22.440 --> 1:15:28.520
 so I thought I would at least have one day before the news would sort of get out.

1:15:28.520 --> 1:15:36.200
 The on your own aspects had also an element of quite, it was quite a powerful element

1:15:36.200 --> 1:15:43.080
 of the uncertainty that lies ahead, but can you also just briefly talk about, for example

1:15:43.080 --> 1:15:49.920
 I play guitar as a hobby for fun, and whenever I play people are super positive, super friendly,

1:15:49.920 --> 1:15:52.680
 they're like, this is awesome, this is great.

1:15:52.680 --> 1:15:57.520
 But sometimes I enter as an outside observer, I enter the programming community and there

1:15:57.520 --> 1:16:05.560
 seems to sometimes be camps on whatever the topic, and the two camps, the two or plus

1:16:05.560 --> 1:16:11.700
 camps, are often pretty harsh at criticizing the opposing camps.

1:16:11.700 --> 1:16:14.880
 As an onlooker, I may be totally wrong on this, but what do you think of this?

1:16:14.880 --> 1:16:19.760
 Yeah, holy wars are sort of a favorite activity in the programming community.

1:16:19.760 --> 1:16:22.120
 And what is the psychology behind that?

1:16:22.120 --> 1:16:25.120
 Is that okay for a healthy community to have?

1:16:25.120 --> 1:16:29.760
 Is that a productive force ultimately for the evolution of a language?

1:16:29.760 --> 1:16:39.080
 Well, if everybody is patting each other on the back and never telling the truth, it would

1:16:39.080 --> 1:16:40.840
 not be a good thing.

1:16:40.840 --> 1:16:52.760
 I think there is a middle ground where sort of being nasty to each other is not okay,

1:16:52.760 --> 1:17:01.760
 but there is a middle ground where there is healthy ongoing criticism and feedback that

1:17:01.760 --> 1:17:04.780
 is very productive.

1:17:04.780 --> 1:17:07.760
 And you mean at every level you see that.

1:17:07.760 --> 1:17:17.760
 I mean, someone proposes to fix a very small issue in a code base, chances are that some

1:17:17.760 --> 1:17:27.080
 reviewer will sort of respond by saying, well, actually, you can do it better the other way.

1:17:27.080 --> 1:17:34.360
 When it comes to deciding on the future of the Python core developer community, we now

1:17:34.360 --> 1:17:41.160
 have, I think, five or six competing proposals for a constitution.

1:17:41.160 --> 1:17:48.040
 So that future, do you have a fear of that future, do you have a hope for that future?

1:17:48.040 --> 1:17:51.280
 I'm very confident about that future.

1:17:51.280 --> 1:17:58.920
 By and large, I think that the debate has been very healthy and productive.

1:17:58.920 --> 1:18:07.680
 And I actually, when I wrote that resignation email, I knew that Python was in a very good

1:18:07.680 --> 1:18:16.840
 spot and that the Python core developer community, the group of 50 or 100 people who sort of

1:18:16.840 --> 1:18:24.720
 write or review most of the code that goes into Python, those people get along very well

1:18:24.720 --> 1:18:27.680
 most of the time.

1:18:27.680 --> 1:18:40.120
 A large number of different areas of expertise are represented, different levels of experience

1:18:40.120 --> 1:18:45.440
 in the Python core dev community, different levels of experience completely outside it

1:18:45.440 --> 1:18:53.040
 in software development in general, large systems, small systems, embedded systems.

1:18:53.040 --> 1:19:03.880
 So I felt okay resigning because I knew that the community can really take care of itself.

1:19:03.880 --> 1:19:12.360
 And out of a grab bag of future feature developments, let me ask if you can comment, maybe on all

1:19:12.360 --> 1:19:19.120
 very quickly, concurrent programming, parallel computing, async IO.

1:19:19.120 --> 1:19:24.880
 These are things that people have expressed hope, complained about, whatever, have discussed

1:19:24.880 --> 1:19:25.880
 on Reddit.

1:19:25.880 --> 1:19:32.200
 Async IO, so the parallelization in general, packaging, I was totally clueless on this.

1:19:32.200 --> 1:19:38.600
 I just used pip to install stuff, but apparently there's pipenv, poetry, there's these dependency

1:19:38.600 --> 1:19:41.300
 packaging systems that manage dependencies and so on.

1:19:41.300 --> 1:19:45.520
 They're emerging and there's a lot of confusion about what's the right thing to use.

1:19:45.520 --> 1:19:56.360
 Then also functional programming, are we going to get more functional programming or not,

1:19:56.360 --> 1:19:59.040
 this kind of idea.

1:19:59.040 --> 1:20:08.280
 And of course the GIL connected to the parallelization, I suppose, the global interpreter lock problem.

1:20:08.280 --> 1:20:12.800
 Can you just comment on whichever you want to comment on?

1:20:12.800 --> 1:20:25.440
 Well, let's take the GIL and parallelization and async IO as one topic.

1:20:25.440 --> 1:20:35.820
 I'm not that hopeful that Python will develop into a sort of high concurrency, high parallelism

1:20:35.820 --> 1:20:37.960
 language.

1:20:37.960 --> 1:20:44.800
 That's sort of the way the language is designed, the way most users use the language, the way

1:20:44.800 --> 1:20:50.280
 the language is implemented, all make that a pretty unlikely future.

1:20:50.280 --> 1:20:56.040
 So you think it might not even need to, really the way people use it, it might not be something

1:20:56.040 --> 1:20:58.160
 that should be of great concern.

1:20:58.160 --> 1:21:05.620
 I think async IO is a special case because it sort of allows overlapping IO and only

1:21:05.620 --> 1:21:18.160
 IO and that is a sort of best practice of supporting very high throughput IO, many connections

1:21:18.160 --> 1:21:21.680
 per second.

1:21:21.680 --> 1:21:22.780
 I'm not worried about that.

1:21:22.780 --> 1:21:25.280
 I think async IO will evolve.

1:21:25.280 --> 1:21:27.440
 There are a couple of competing packages.

1:21:27.440 --> 1:21:36.800
 We have some very smart people who are sort of pushing us to make async IO better.

1:21:36.800 --> 1:21:43.800
 Parallel computing, I think that Python is not the language for that.

1:21:43.800 --> 1:21:53.560
 There are ways to work around it, but you can't expect to write an algorithm in Python

1:21:53.560 --> 1:21:57.440
 and have a compiler automatically parallelize that.

1:21:57.440 --> 1:22:03.520
 What you can do is use a package like NumPy and there are a bunch of other very powerful

1:22:03.520 --> 1:22:12.480
 packages that sort of use all the CPUs available because you tell the package, here's the data,

1:22:12.480 --> 1:22:19.040
 here's the abstract operation to apply over it, go at it, and then we're back in the C++

1:22:19.040 --> 1:22:20.040
 world.

1:22:20.040 --> 1:22:24.600
 Those packages are themselves implemented usually in C++.

1:22:24.600 --> 1:22:28.000
 That's where TensorFlow and all these packages come in, where they parallelize across GPUs,

1:22:28.000 --> 1:22:30.480
 for example, they take care of that for you.

1:22:30.480 --> 1:22:36.600
 In terms of packaging, can you comment on the future of packaging in Python?

1:22:36.600 --> 1:22:42.640
 Packaging has always been my least favorite topic.

1:22:42.640 --> 1:22:55.600
 It's a really tough problem because the OS and the platform want to own packaging, but

1:22:55.600 --> 1:23:01.000
 their packaging solution is not specific to a language.

1:23:01.000 --> 1:23:07.480
 If you take Linux, there are two competing packaging solutions for Linux or for Unix

1:23:07.480 --> 1:23:15.000
 in general, but they all work across all languages.

1:23:15.000 --> 1:23:24.760
 Several languages like Node, JavaScript, Ruby, and Python all have their own packaging solutions

1:23:24.760 --> 1:23:29.480
 that only work within the ecosystem of that language.

1:23:29.480 --> 1:23:31.920
 What should you use?

1:23:31.920 --> 1:23:34.560
 That is a tough problem.

1:23:34.560 --> 1:23:43.520
 My own approach is I use the system packaging system to install Python, and I use the Python

1:23:43.520 --> 1:23:49.280
 packaging system then to install third party Python packages.

1:23:49.280 --> 1:23:51.480
 That's what most people do.

1:23:51.480 --> 1:23:56.400
 Ten years ago, Python packaging was really a terrible situation.

1:23:56.400 --> 1:24:05.360
 Nowadays, pip is the future, there is a separate ecosystem for numerical and scientific Python

1:24:05.360 --> 1:24:08.200
 based on Anaconda.

1:24:08.200 --> 1:24:09.760
 Those two can live together.

1:24:09.760 --> 1:24:13.600
 I don't think there is a need for more than that.

1:24:13.600 --> 1:24:14.600
 That's packaging.

1:24:14.600 --> 1:24:18.720
 Well, at least for me, that's where I've been extremely happy.

1:24:18.720 --> 1:24:22.320
 I didn't even know this was an issue until it was brought up.

1:24:22.320 --> 1:24:27.600
 In the interest of time, let me sort of skip through a million other questions I have.

1:24:27.600 --> 1:24:32.880
 So I watched the five and a half hour oral history that you've done with the Computer

1:24:32.880 --> 1:24:37.600
 History Museum, and the nice thing about it, it gave this, because of the linear progression

1:24:37.600 --> 1:24:44.480
 of the interview, it gave this feeling of a life, you know, a life well lived with interesting

1:24:44.480 --> 1:24:52.160
 things in it, sort of a pretty, I would say a good spend of this little existence we have

1:24:52.160 --> 1:24:53.160
 on Earth.

1:24:53.160 --> 1:24:59.840
 So, outside of your family, looking back, what about this journey are you really proud

1:24:59.840 --> 1:25:00.840
 of?

1:25:00.840 --> 1:25:07.040
 Are there moments that stand out, accomplishments, ideas?

1:25:07.040 --> 1:25:14.040
 Is it the creation of Python itself that stands out as a thing that you look back and say,

1:25:14.040 --> 1:25:16.480
 damn, I did pretty good there?

1:25:16.480 --> 1:25:25.520
 Well, I would say that Python is definitely the best thing I've ever done, and I wouldn't

1:25:25.520 --> 1:25:36.560
 sort of say just the creation of Python, but the way I sort of raised Python, like a baby.

1:25:36.560 --> 1:25:42.480
 I didn't just conceive a child, but I raised a child, and now I'm setting the child free

1:25:42.480 --> 1:25:50.200
 in the world, and I've set up the child to sort of be able to take care of himself, and

1:25:50.200 --> 1:25:52.640
 I'm very proud of that.

1:25:52.640 --> 1:25:56.740
 And as the announcer of Monty Python's Flying Circus used to say, and now for something

1:25:56.740 --> 1:26:02.280
 completely different, do you have a favorite Monty Python moment, or a moment in Hitchhiker's

1:26:02.280 --> 1:26:07.720
 Guide, or any other literature show or movie that cracks you up when you think about it?

1:26:07.720 --> 1:26:11.320
 You can always play me the dead parrot sketch.

1:26:11.320 --> 1:26:13.680
 Oh, that's brilliant.

1:26:13.680 --> 1:26:14.680
 That's my favorite as well.

1:26:14.680 --> 1:26:15.680
 It's pushing up the daisies.

1:26:15.680 --> 1:26:20.680
 Okay, Greta, thank you so much for talking with me today.

1:26:20.680 --> 1:26:44.080
 Lex, this has been a great conversation.