← Lex Fridman

François Chollet: Measures of Intelligence

Episode 1202020-08-31English

Guests: François Chollet

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§01Transcript · 00:00–09:13

00:00The following is a conversation with Francois Chollet,

00:03his second time on the podcast.

00:05He's both a world-class engineer and a philosopher

00:09in the realm of deep learning and artificial intelligence.

00:13This time, we talk a lot about his paper titled

00:16On the Measure of Intelligence

00:18that discusses how we might define

00:20and measure general intelligence in our computing machinery.

00:24Quick summary of the sponsors,

00:26Babbel, Masterclass, and Cash App.

00:29Click the sponsor links in the description

00:31to get a discount and to support this podcast.

00:34As a side note, let me say that the serious,

00:36rigorous scientific study

00:38of artificial general intelligence is a rare thing.

00:42The mainstream machine learning community

00:43works on very narrow AI with very narrow benchmarks.

00:47This is very good for incremental

00:49and sometimes big incremental progress.

00:53On the other hand, the outside the mainstream,

00:56renegade, you could say, AGI community

00:59works on approaches that verge on the philosophical

01:03and even the literary without big public benchmarks.

01:07Walking the line between the two worlds is a rare breed,

01:10but it doesn't have to be.

01:12I ran the AGI series at MIT as an attempt

01:15to inspire more people to walk this line.

01:17Deep mind and open AI for a time

01:20and still on occasion walk this line.

01:23Francois Chollet does as well.

01:25I hope to also.

01:27It's a beautiful dream to work towards

01:29and to make real one day.

01:32If you enjoy this thing, subscribe on YouTube,

01:34review it with Five Stars on Apple Podcast,

01:36follow on Spotify, support on Patreon,

01:39or connect with me on Twitter @LexFriedman.

01:42As usual, I'll do a few minutes of ads now

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01:52by clicking the links in the description.

01:54It's the best way to support this podcast.

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05:00And now here's my conversation with Francois Chollet.

05:03What philosophers, thinkers or ideas

05:07had a big impact on you growing up and today?

05:10- So one author that had a big impact on me

05:14when I read his books as a teenager was Jean Piaget,

05:18who is a Swiss psychologist,

05:21is considered to be the father of developmental psychology.

05:25And he has a large body of work

05:27about basically how intelligence develops in children.

05:32And so it's very old work,

05:35like most of it is from the 1930s, 1940s.

05:39So it's not quite up to date.

05:40It's actually superseded by many newer developments

05:43in developmental psychology.

05:45But to me, it was very, very interesting,

05:48very striking and actually shaped the early ways

05:51in which I started to think about the mind

05:53and the development of intelligence as a teenager.

05:56- His actual ideas or the way he thought about it

05:58or just the fact that you could think

05:59about the developing mind at all?

06:01- I guess both.

06:02Jean Piaget is the author that reintroduced me

06:04to the notion that intelligence and the mind

06:07is something that you construct throughout your life

06:11and that children construct it in stages.

06:15And I thought that was a very interesting idea,

06:17which is, of course, very relevant to AI,

06:20to building artificial minds.

06:22Another book that I read around the same time

06:25that had a big impact on me,

06:27and there was actually a little bit of overlap

06:32with Jean Piaget as well,

06:32and I read it around the same time,

06:35is Jeff Hawkins' "On Intelligence," which is a classic.

06:39And he has this vision of the mind

06:42as a multi-scale hierarchy of temporal prediction modules.

06:47And these ideas really resonated with me,

06:50like the notion of a modular hierarchy

06:53of potentially of compression functions

07:00or prediction functions.

07:01I thought it was really, really interesting.

07:03And it really shaped the way I started thinking

07:07about how to build minds.

07:09- The hierarchical nature, which aspect.

07:13Also, he's a neuroscientist, so he was thinking actual,

07:17he was basically talking about how our mind works.

07:20- Yeah, the notion that cognition is prediction

07:23was an idea that was kind of new to me at the time

07:25and that I really loved at the time.

07:27And yeah, and the notion that there are multiple scales

07:31of processing in the brain.

07:34- The hierarchy. - Yes.

07:36- This was before deep learning.

07:38These ideas of hierarchies in AI

07:41have been around for a long time,

07:43even before "On Intelligence,"

07:45they've been around since the 1980s.

07:47And yeah, that was before deep learning,

07:50but of course, I think these ideas really found

07:52their practical implementation in deep learning.

07:58- What about the memory side of things?

07:59I think he was talking about knowledge representation.

08:02Do you think about memory a lot?

08:04One way you can think of neural networks

08:06as a kind of memory, you're memorizing things,

08:10but it doesn't seem to be the kind of memory

08:14that's in our brains, or it doesn't have

08:17the same rich complexity, long-term nature

08:19that's in our brains. - Yes.

08:21The brain is more of a sparse access memory

08:23so that you can actually retrieve very precisely

08:27like bits of your experience.

08:30- The retrieval aspect, you can like introspect,

08:33you can ask yourself questions, I guess.

08:36You can program your own memory,

08:38and language is actually the tool you use to do that.

08:41I think language is a kind of operating system for the mind.

08:46And you use language, well, one of the uses of language

08:49is as a query that you run over your own memory.

08:53You use words as keys to retrieve specific experiences

08:57or specific concepts, specific thoughts.

09:00Like language is a way you store thoughts,

09:02not just in writing, in the physical world,

09:04but also in your own mind.

09:06And it's also how you retrieve them.

09:07Like imagine if you didn't have language,

09:10then you would have to, you would not really have

09:13a self-internally triggered way of retrieving past thoughts.

§02Transcript · 09:18–18:46

09:18You would have to rely on external experiences.

09:21For instance, you see a specific site,

09:24you smell a specific smell, and that brings up memories,

09:26but you would not really have a way to deliberately

09:30access these memories without language.

09:32- Well, the interesting thing you mentioned

09:34is you can also program the memory.

09:37You can change it, probably with language.

09:40- Yeah, using language, yes.

09:41- Well, let me ask you a Chomsky question,

09:44which is like, first of all,

09:46do you think language is like fundamental,

09:49like there's turtles, what's at the bottom of the turtles?

09:54They don't go, it can't be turtles all the way down.

09:57Is language at the bottom of cognition of everything?

10:00Is like language the fundamental,

10:03aspect of like what it means to be a thinking thing?

10:08- No, I don't think so.

10:12I think language is--

10:12- You disagree with Norm Chomsky?

10:14- Yes, I think language is a layer on top of cognition.

10:17So it is fundamental to cognition in the sense that,

10:21to use a computing metaphor, I see language

10:24as the operating system of the brain, of the human mind.

10:29And the operating system, you know,

10:31is a layer on top of the computer.

10:33The computer exists before the operating system,

10:36but the operating system is how you make it truly useful.

10:39- And the operating system is most likely Windows,

10:42not Linux, 'cause language is messy.

10:45- Yeah, it's messy and it's pretty difficult

10:49to inspect it, introspect it.

10:53- How do you think about language?

10:55Like we use actually sort of human interpretable language,

11:00but is there something like deeper,

11:03that's closer to like logical type of statements?

11:07Like, yeah, what is the nature of language, do you think?

11:13Like is there something deeper

11:17than like the syntactic rules we construct?

11:19Is there something that doesn't require utterances

11:22or writing or so on?

11:25- Are you asking about the possibility that could exist?

11:29Languages for thinking that are not made of words?

11:32- Yeah.

11:33- Yeah, I think so.

11:34I think, so the mind is layers, right?

11:38And language is almost like the outermost,

11:41the uppermost layer.

11:43But before we think in words,

11:46I think we think in terms of emotion in space

11:51and we think in terms of physical actions.

11:54And I think babies in particular

11:56probably express these thoughts in terms of the actions

12:01that they've seen or that they can perform.

12:03And in terms of motions of objects in their environment

12:08before they start thinking in terms of words.

12:10- It's amazing to think about that

12:13as the building blocks of language.

12:16So like the kind of actions and ways the babies

12:20see the world as like more fundamental

12:23than the beautiful Shakespearean language

12:26you construct on top of it.

12:27And we probably don't have any idea

12:30what that looks like, right?

12:32'Cause it's important for them trying to engineer it

12:35into AI systems.

12:37- I think visual analogies and motion

12:42is a fundamental building block of the mind.

12:45And you actually see it reflected in language.

12:48Like language is full of spatial metaphors.

12:51And when you think about things,

12:53I consider myself very much as a visual thinker.

12:57You often express these thoughts by using things

13:02like visualizing concepts in 2D space

13:07or like you solve problems by imagining yourself

13:12navigating a concept space.

13:15I don't know if you have this sort of experience.

13:17- You said visualizing concept space.

13:19So like, so I certainly think about

13:22I certainly visualize mathematical concepts,

13:27but you mean like in concept space?

13:31Visually you're embedding ideas

13:34into a three dimensional space

13:37you can explore with your mind essentially.

13:38- You mean more like 2D, but yeah.

13:40- 2D?

13:41You're a flatlander.

13:43You're, okay.

13:45No, I do not.

13:49I always have to, before I jump from concept to concept,

13:52I have to put it back down on paper.

13:57It has to be on paper.

13:58I can only travel on a 2D paper, not inside my mind.

14:03You're able to move inside your mind.

14:05- But even if you're writing like a paper, for instance,

14:07don't you have like a spatial representation of your paper?

14:11Like you visualize where ideas lie topologically

14:16in relationship to other ideas,

14:19kind of like a subway map of the ideas in your paper?

14:22- Yeah, that's true.

14:23I mean, there is, in papers, I don't know about you,

14:27but it feels like there's a destination.

14:30There's a key idea that you wanna arrive at

14:36and a lot of it is in the fog

14:39and you're trying to kind of, it's almost like,

14:45what's that called when you do a path planning search

14:49from both directions, from the start and from the end?

14:51And then you find, you do like shortest path,

14:54but in game playing, you do this with like A star

14:59from both sides.

15:01- And you see where we're on the join.

15:03- Yeah, so you kind of do, at least for me,

15:05I think like, first of all, just exploring from the start,

15:08from like first principles, what do I know?

15:12What can I start proving from that?

15:15And then from the destination, if you start backtracking,

15:20if I want to show some kind of sets of ideas,

15:25what would it take to show them?

15:26And you kind of backtrack.

15:28But yeah, I don't think I'm doing all that in my mind,

15:31though, like I'm putting it down on paper.

15:33- Do you use mind maps to organize your ideas?

15:35Yeah, I like mind maps.

15:37I'm that kind of person.

15:37- Let's get into this 'cause it's,

15:39I've been so jealous of people, I haven't really tried it.

15:42I've been jealous of people that seem to like,

15:45they get like this fire of passion in their eyes

15:48'cause everything starts making sense.

15:50It's like Tom Cruise in the movie

15:52was like moving stuff around.

15:53Some of the most brilliant people I know use mind maps.

15:55I haven't tried really.

15:57Can you explain what the hell a mind map is?

16:01- I guess a mind map is a way to make

16:03kind of like the mess inside your mind

16:05to just put it on paper

16:08so that you gain more control over it.

16:10It's a way to organize things on paper.

16:13And as kind of like a consequence

16:16of organizing things on paper,

16:18it starts being more organized inside your own mind.

16:20- So what does that look like?

16:21You put, like, do you have an example?

16:24Like, what's the first thing you write on paper?

16:27What's the second thing you write?

16:29- I mean, typically you draw a mind map

16:31to organize the way you think about a topic.

16:34So you would start by writing down

16:37like the key concept about that topic.

16:39Like you would write intelligence or something.

16:42And then you would start adding associative connections.

16:45Like, what do you think about

16:46when you think about intelligence?

16:48What do you think are the key elements of intelligence?

16:50So maybe you would have language, for instance,

16:52and you'd have motion.

16:53And so you would start drawing notes with these things.

16:55And then you would see,

16:56what do you think about when you think about motion?

16:58And so on, and you would go like that, like a tree.

17:00- It's a tree or a tree mostly,

17:03or is it a graph too, like a tree?

17:05- Oh, it's more of a graph than a tree.

17:08And it's not limited to just writing down words.

17:13You can also draw things.

17:15And it's not supposed to be purely hierarchical, right?

17:19Like you can, the point is that you can start,

17:23once you start writing it down,

17:24you can start reorganizing it so that it makes more sense,

17:27so that it's connected in a more effective way.

17:29- See, but I'm so OCD that you just mentioned intelligence

17:35and then language and motion.

17:37I would start becoming paranoid

17:39that the categorization is imperfect.

17:42Like that I would become paralyzed with the mind map

17:47that like this may not be.

17:49So like the, even though you're just doing

17:52associative kind of connections,

17:55there's an implied hierarchy that's emerging.

17:58And I would start becoming paranoid

17:59that it's not the proper hierarchy.

18:02So you're not just, one way to see mind maps

18:05is you're putting thoughts on paper.

18:07It's like a stream of consciousness,

18:10but then you can also start getting paranoid.

18:12Well, is this the right hierarchy?

18:15- Sure, but it's mind maps, your mind map.

18:17You're free to draw anything you want.

18:19You're free to draw any connection you want.

18:20And you can just make a different mind map

18:23if you think the central node is not the right node.

18:26- Yeah, I suppose there's a fear of being wrong.

18:29- If you want to organize your ideas

18:32by writing down what you think,

18:35which I think is very effective.

18:37Like how do you know what you think about something

18:40if you don't write it down, right?

18:42If you do that, the thing is that it imposes

18:46much more syntactic structure over your ideas,

§03Transcript · 18:50–28:26

18:50which is not required with a mind map.

18:51So a mind map is kind of like a lower level,

18:54more freehand way of organizing your thoughts.

18:57And once you've drawn it,

18:59then you can start actually voicing your thoughts

19:03in terms of paragraphs.

19:05- It's a two dimensional aspect of layout too, right?

19:08And it's a kind of flower, I guess, you start.

19:12There's usually, you want to start with a central concept?

19:15- Yes. - And then you move on.

19:16- Typically it ends up more like a subway map.

19:19So it ends up more like a graph, a topological graph.

19:22- Without a root node.

19:23- Yeah, so like in a subway map,

19:25there are some nodes that are more connected than others.

19:27And there are some nodes that are more important than others.

19:30So there are destinations,

19:32but it's not gonna be purely like a tree, for instance.

19:36- Yeah, it's fascinating to think

19:38if there's something to that about the way our mind thinks.

19:42By the way, I just kind of remembered obvious thing

19:45that I have probably thousands of documents

19:49in Google Doc at this point that are bullet point lists,

19:54which is, you can probably map a mind map

19:57to a bullet point list.

19:59It's the same, it's a, no, it's not, it's a tree.

20:05It's a tree, yeah.

20:06So I create trees,

20:07but also they don't have the visual element.

20:10Like, I guess I'm comfortable with the structure.

20:13It feels like, the narrowness,

20:15the constraints feel more comforting.

20:18- If you have thousands of documents

20:20with your own thoughts in Google Docs,

20:23why don't you write some kind of search engine,

20:26like maybe a mind map, a piece of software,

20:30a mind mapping software where you write down a concept

20:33and then it gives you sentences or paragraphs

20:37from your thousands Google Docs document

20:39that match this concept.

20:41- The problem is it's so deeply, unlike mind maps,

20:45it's so deeply rooted in natural language.

20:48So it's not semantically searchable, I would say,

20:53'cause the categories are very,

20:57you kind of mentioned intelligence, language, and motion.

21:00They're very strong semantic.

21:02Like, it feels like the mind map forces you

21:05to be semantically clear and specific.

21:09The bullet points list I have

21:11are sparse, disparate thoughts

21:16that poetically represent a category,

21:21like motion, as opposed to saying motion.

21:24So unfortunately, that's the same problem with the internet.

21:28That's why the idea of semantic web is difficult to get.

21:31Most language on the internet is a giant mess

21:37of natural language that's hard to interpret.

21:40So do you think there's something to mind maps as,

21:46you actually originally brought it up

21:48as we were talking about kind of cognition and language.

21:53Do you think there's something to mind maps

21:55about how our brain actually deals,

21:58like, think reasons about things?

22:00- It's possible.

22:02I think it's reasonable to assume

22:04that there is some level of topological processing

22:09in the brain, that the brain is very associative in nature.

22:15And I also believe that a topological space

22:20is a better medium to encode thoughts

22:25than a geometric space.

22:27So I think--

22:28- What's the difference in a topological

22:29and a geometric space?

22:31- Well, if you're talking about topologies,

22:34then points are either connected or not.

22:36So a topology is more like a subway map.

22:38And geometry is when you're interested

22:41in the distance between things.

22:43And in subway maps, you don't really have

22:45the concept of distance.

22:46You only have the concept of whether there is a train

22:48going from station A to station B.

22:51And what we do in deep learning

22:54is that we're actually dealing with geometric spaces.

22:57We are dealing with concept vectors, word vectors,

23:01that have a distance between them

23:03which is expressed in terms of that product.

23:05We are not really building topological models usually.

23:10- I think you're absolutely right.

23:11Like distance is a fundamental importance in deep learning.

23:16I mean, it's the continuous aspect of it.

23:19- Yes, because everything is a vector

23:21and everything has to be a vector

23:22because everything has to be differentiable.

23:24If your space is discrete, it's no longer differentiable.

23:26You cannot do deep learning in it anymore.

23:29Well, you could, but you could only do it

23:31by embedding it in a bigger continuous space.

23:35So if you do topology in the context of deep learning,

23:39you have to do it by embedding your topology

23:41in a geometry.

23:41- Well, let me zoom out for a second.

23:46Let's get into your paper on the measure of intelligence

23:49that you put out in 2019?

23:52- Yes.

23:53- Okay.

23:54- November.

23:55- November.

23:56Yeah, remember 2019?

23:59That was a different time.

24:01- Yeah, I remember.

24:02I still remember.

24:03(Lex laughing)

24:06- It feels like a different world.

24:09You could travel, you could actually go outside

24:12and see friends.

24:14- Yeah.

24:16Let me ask the most absurd question.

24:18I think there's some non-zero probability

24:21there'll be a textbook one day,

24:23like 200 years from now, on artificial intelligence,

24:27or it'll be called just intelligence

24:30'cause humans will already be gone.

24:32It'll be your picture with a quote.

24:35One of the early biological systems

24:39would consider the nature of intelligence,

24:41and there'll be a definition

24:43of how they thought about intelligence,

24:45which is one of the things you do in your paper

24:46on measure of intelligence is to ask,

24:49well, what is intelligence

24:52and how to test for intelligence and so on.

24:55So is there a spiffy quote about what is intelligence?

25:00What is the definition of intelligence,

25:03according to Francois Chollet?

25:06- Yeah, so do you think the super intelligent AIs

25:10of the future will want to remember us

25:13the way we remember humans from the past?

25:15And do you think they won't be ashamed

25:19of having a biological origin?

25:21- No, I think it would be a niche topic.

25:24It won't be that interesting,

25:25but it'll be like the people that study

25:29in certain contexts, like historical civilization

25:32that no longer exist, the Aztecs,

25:34and so on, that's how it'll be seen.

25:38And it'll be studied in also the context on social media,

25:42there'll be hashtags about the atrocity committed

25:47to human beings when the robots finally got rid of them.

25:52Like it was a mistake, it'll be seen as a giant mistake,

25:57but ultimately in the name of progress,

26:00and it created a better world

26:01because humans were over-consuming the resources,

26:05and they were not very rational,

26:07and were destructive in the end in terms of productivity,

26:11and putting more love in the world.

26:13And so within that context, there'll be a chapter

26:16about these biological systems.

26:17- Seems you have a very detailed vision of that hit here.

26:20You should write a sci-fi novel about it.

26:22- I'm working on a sci-fi novel currently, yes.

26:26- Yeah, so-- - Self-published, yeah.

26:29- The definition of intelligence,

26:30so intelligence is the efficiency

26:34with which you acquire new skills,

26:38tasks that you did not previously know about,

26:41that you did not prepare for, right?

26:44So it is not, intelligence is not skill itself,

26:47it's not what you know, it's not what you can do,

26:50it's how well and how efficiently you can learn new things.

26:54- New things. - Yes.

26:56- The idea of newness there

26:58seems to be fundamentally important.

27:01- Yes, so you would see intelligence on display,

27:04for instance, whenever you see a human being

27:08or an AI creature adapt to a new environment

27:12that it does not see before,

27:13that its creators did not anticipate.

27:16When you see adaptation, when you see improvisation,

27:19when you see generalization, that's intelligence.

27:22In reverse, if you have a system

27:24that when you put it in a slightly new environment,

27:27it cannot adapt, it cannot improvise,

27:29it cannot deviate from what it's hard-coded to do

27:33or what it has been trained to do,

27:37that is a system that is not intelligent.

27:41There's actually a quote from Einstein

27:43that captures this idea, which is,

27:46"The measure of intelligence is the ability to change."

27:50I like that quote, I think it captures

27:53at least part of this idea.

27:54- You know, there might be something interesting

27:56about the difference between your definition and Einstein's.

27:59I mean, he's just being Einstein and clever,

28:03but acquisition of new ability to deal with new things

28:09versus ability to just change,

28:16what's the difference between those two things?

28:19So just change in itself,

28:22do you think there's something to that?

28:24Just being able to change.

28:26- Yes, being able to adapt.

§04Transcript · 28:28–37:27

28:28So not change, but certainly a change in direction,

28:33being able to adapt yourself to your environment.

28:36- Whatever the environment is.

28:38- That's a big part of intelligence, yes.

28:40And intelligence is most precisely,

28:43how efficiently you're able to adapt,

28:45how efficiently you're able to

28:47basically master your environment,

28:49how efficiently you can acquire new skills.

28:52And I think there's a big distinction to be drawn

28:55between intelligence, which is a process,

28:59and the output of that process, which is skill.

29:03So for instance, if you have a very smart human programmer

29:08that considers the game of chess

29:10and that writes down a static program that can play chess,

29:15then the intelligence is the process

29:19of developing that program.

29:20But the program itself is just encoding

29:25the output artifacts of that process.

29:28The program itself is not intelligent.

29:30And the way you tell it's not intelligent

29:31is that if you put it in a different context,

29:34you ask it to play Go or something,

29:36it's not gonna be able to perform well

29:37without human involvement.

29:38Because the source of intelligence,

29:41the entity that is capable of that process

29:43is the human programmer.

29:44So we should be able to tell the difference

29:47between the process and its output.

29:50We should not confuse the output and the process.

29:53It's the same as, do not confuse a road building company

29:58and one specific road,

30:00because one specific road takes you from point A to point B,

30:03but a road building company can take you from,

30:06can make a path from anywhere to anywhere else.

30:08- Yeah, that's beautifully put.

30:10But it's also, to play devil's advocate a little bit,

30:14it's possible that there is something more fundamental

30:19than us humans.

30:21So you kind of said the programmer creates

30:24the difference between the choir of the skill

30:29and the skill itself.

30:31There could be something,

30:32like you could argue the universe is more intelligent.

30:36Like the deep, the base intelligence

30:40that we should be trying to measure

30:43is something that created humans.

30:45We should be measuring God,

30:48or the source of the universe,

30:51as opposed to, like there could be a deeper intelligence.

30:55- Sure.

30:55- There's always deeper intelligence, I guess.

30:57- You can argue that,

30:58but that does not take anything away

31:00from the fact that humans are intelligent.

31:01And you can tell that

31:03because they are capable of adaptation and generality.

31:07And you see that in particular in the fact that

31:10humans are capable of handling situations and tasks

31:16that are quite different from anything

31:19that any of our evolutionary ancestors has ever encountered.

31:24So we are capable of generalizing very much

31:27out of distribution,

31:28if you consider our evolutionary history

31:30as being in a way our training data.

31:32- Of course, evolutionary biologists would argue

31:35that we're not going too far out of the distribution.

31:37We're like mapping the skills we've learned previously,

31:41desperately trying to like jam them

31:43into like these new situations.

31:47- I mean, there's definitely a little bit of that,

31:49but it's pretty clear to me that we're able to,

31:52you know, most of the things we do any given day

31:56in our modern civilization

31:58are things that are very, very different

32:00from what our ancestors a million years ago

32:03would have been doing in a given day.

32:05And our environment is very different.

32:07So I agree that everything we do,

32:12we do it with cognitive building blocks

32:14that we acquired over the course of evolution, right?

32:17And that anchors our cognition to certain contexts,

32:22which is the human condition very much.

32:25But still our mind is capable

32:27of a pretty remarkable degree of generality,

32:30far beyond anything we can create

32:32in artificial systems today.

32:34Like the degree in which the mind can generalize

32:37from its evolutionary history,

32:40can generalize away from its evolutionary history

32:44is much greater than the degree

32:46to which a deep learning system today

32:48can generalize away from its training data.

32:51- And like the key point you're making,

32:52which I think is quite beautiful,

32:53is like we shouldn't measure,

32:57if we're talking about measurement,

32:58we shouldn't measure the skill.

33:00We should measure like the creation of the new skill,

33:04the ability to create that new skill.

33:06- Yes.

33:07- But it's tempting.

33:08It's weird because the skill

33:11is a little bit of a small window

33:13into the system.

33:16So whenever you have a lot of skills,

33:18it's tempting to measure the skills.

33:21- Yes.

33:22I mean, the skill is the only thing

33:23you can objectively measure.

33:26But yeah, so the thing to keep in mind

33:29is that when you see skill in a human,

33:33it gives you a strong signal

33:37that that human is intelligent

33:39because you know they weren't born with that skill,

33:42typically.

33:42Like you see a very strong chess player,

33:45maybe you're a very strong chess player yourself.

33:47- I think you're saying that 'cause I'm Russian

33:51and now you're prejudiced.

33:52You assume all Russians are good at chess.

33:54- I'm biased, exactly.

33:55- I'm biased.

33:56Well, you're definitely.

33:57- Cultural bias.

33:58So if you see a very strong chess player,

34:01you know they weren't born knowing how to play chess.

34:05So they had to acquire that skill

34:07with their limited resources,

34:09with their limited lifetime.

34:10And you know, they did that

34:13because they are generally intelligent.

34:15And so they may as well have acquired any other skill.

34:18You know they have this potential.

34:21And on the other hand,

34:22if you see a computer playing chess,

34:25you cannot make the same assumptions

34:27because you cannot just assume

34:29the computer is generally intelligent.

34:30The computer may be born knowing how to play chess

34:35in the sense that it may have been programmed

34:37by a human that has understood chess for the computer

34:40and that has just encoded the output

34:44of that understanding and aesthetic program.

34:46And that program is not intelligent.

34:49- So let's zoom out just for a second

34:51and say like, what is the goal

34:54of the "On the Measure of Intelligence" paper?

34:57Like what do you hope to achieve with it?

34:59- So the goal of the paper

35:00is to clear up some longstanding misunderstandings

35:04about the way we've been conceptualizing intelligence

35:08in the AI community.

35:09And in the way we've been evaluating progress in AI.

35:14There's been a lot of progress recently in machine learning

35:19and people are extrapolating from that progress

35:22that we are about to solve general intelligence.

35:26And if you want to be able to evaluate these statements,

35:30you need to precisely define what you're talking about

35:33when you're talking about general intelligence.

35:35And you need a formal way, a reliable way

35:40to measure how much intelligence,

35:42how much general intelligence a system processes.

35:46And ideally this measure of intelligence

35:48should be actionable.

35:50So it should not just describe what intelligence is.

35:55It should not just be a binary indicator

35:57that tells you the system is intelligent or it isn't.

36:01It should be actionable.

36:03It should have explanatory power, right?

36:06So you could use it as a feedback signal.

36:09It would show you the way

36:11towards building more intelligent systems.

36:13- So at the first level,

36:16you draw a distinction between two divergent views

36:18of intelligence.

36:19As we just talked about,

36:23intelligence is a collection of task-specific skills

36:27and a general learning ability.

36:30So what's the difference between

36:31kind of this memorization of skills

36:36and a general learning ability?

36:38We've talked about it a little bit,

36:39but can you try to linger on this topic for a bit?

36:43- Yeah, so the first part of the paper

36:45is an assessment of the different ways

36:49we've been thinking about intelligence

36:50and the different ways we've been evaluating progress

36:53in AI.

36:54And the history of cognitive sciences

36:57has been shaped by two views of the human mind.

37:01And one view is the evolutionary psychology view

37:04in which the mind is a collection

37:08of fairly static, special purpose, ad hoc mechanisms

37:13that have been hard-coded by evolution

37:17over our history as a species over a very long time.

37:21And

37:25early AI researchers,

37:27people like Marvin Minsky, for instance,

§05Transcript · 37:30–47:14

37:30they clearly subscribed to this view.

37:33And they saw the mind as a kind of,

37:36you know, collection of static programs

37:38similar to the programs they would run

37:42on like mainframe computers.

37:43And in fact, I think they very much understood the mind

37:48through the metaphor of the mainframe computer

37:50because it was the tool they were working with, right?

37:53And so you had these static programs,

37:55this collection of very different static programs

37:57operating over a database like memory.

38:00And in this picture, learning was not very important.

38:03Learning was considered to be just memorization.

38:05And in fact, learning is basically not featured

38:10in AI textbooks until the 1980s

38:14with the rise of machine learning.

38:17- It's kind of fun to think about

38:18that learning was the outcast,

38:20like the weird people working on learning,

38:24like the mainstream AI world was,

38:28I mean, I don't know what the best term is,

38:31but it's non-learning.

38:33It was seen as like reasoning

38:36would not be learning-based.

38:38- Yes, it was seen,

38:39it was considered that the mind was a collection

38:42of programs that were primarily logical in nature.

38:46And that's all you needed to do to create a mind

38:49was to write down these programs

38:50and they would operate over knowledge,

38:52which would be stored in some kind of database.

38:55And as long as your database would encompass

38:58everything about the world

38:59and your logical rules were comprehensive,

39:03then you would have a mind.

39:05So the other view of the mind

39:06is the brain as sort of blank slate, right?

39:11This is a very old idea.

39:13You find it in John Locke's writings.

39:16This is the Tabula rasa.

39:17And this is this idea that the mind

39:21is some kind of like information sponge

39:23that starts empty, that starts blank,

39:28and that absorbs knowledge and skills from experience.

39:33So it's a sponge that reflects the complexity of the world,

39:39the complexity of your life experience, essentially.

39:42That everything you know and everything you can do

39:45is a reflection of something you found

39:48in the outside world, essentially.

39:50So this is an idea that's very old,

39:52that was not very popular, for instance, in the 1970s,

39:58but that had gained a lot of vitality recently

40:00with the rise of connectionism, in particular deep learning.

40:04And so today, deep learning is the dominant paradigm in AI.

40:08And I feel like lots of AI researchers

40:12are conceptualizing the mind via a deep learning metaphor.

40:16Like they see the mind as a kind of

40:19randomly initialized neural network

40:22that starts blank when you're born,

40:24and then that gets trained via exposure to training data

40:27that acquires knowledge and skills

40:29via exposure to training data.

40:31- By the way, it's a small tangent.

40:33I feel like people who are thinking about intelligence

40:38are not conceptualizing it that way.

40:41I actually haven't met too many people

40:43who believe that a neural network will be able to reason,

40:48who seriously think that, rigorously,

40:51'cause I think it's actually an interesting worldview.

40:54And we'll talk about it more,

40:56but it's been impressive

40:58what neural networks have been able to accomplish.

41:02And to me, I don't know, you might disagree,

41:04but it's an open question whether like scaling size

41:09eventually might lead to incredible results to us,

41:14mere humans will appear as if it's general.

41:17- I mean, if you ask people

41:18who are seriously thinking about intelligence,

41:20they will definitely not say that all you need to do

41:23is like the mind is just a neural network.

41:26However, it's actually a view that's very popular,

41:30I think, in the deep learning community,

41:31that many people are kind of conceptually,

41:35intellectually lazy about it.

41:37- Right.

41:38- But I guess what I'm saying exactly right,

41:40is I haven't met many people,

41:44and I think it would be interesting

41:46to meet a person who is not intellectually lazy

41:48about this particular topic,

41:50and still believes that neural networks will go all the way.

41:54I think Yann LeCun is probably closest to that,

41:56would self-supervise. - There are definitely people

41:58who argue that currently planning techniques

42:03are already the way to general artificial intelligence,

42:06that all you need to do is to scale it up

42:09to all the available trained data.

42:12And that's, if you look at the waves

42:16that OpenAI's GPT-3 model has made,

42:19you see echoes of this idea.

42:22- So on that topic, GPT-3, similar to GPT-2, actually,

42:27have captivated some part of the imagination of the public.

42:33There's just a bunch of hype of different kind

42:35that's, I would say it's emergent,

42:37it's not artificially manufactured,

42:39it's just like people just get excited

42:42for some strange reason.

42:43And in the case of GPT-3, which is funny,

42:46that there's, I believe, a couple months delay

42:49from a release to hype.

42:51Maybe I'm not historically correct on that,

42:56but it feels like there was a little bit of a lack of hype,

43:01and then there's a phase shift into hype.

43:04But nevertheless, there's a bunch of cool applications

43:07that seem to captivate the imagination of the public

43:10about what this language model

43:12that's trained in unsupervised way

43:15without any fine tuning is able to achieve.

43:19So what do you make of that?

43:20What are your thoughts about GPT-3?

43:22- Yeah, so I think what's interesting about GPT-3

43:25is the idea that it may be able to learn new tasks

43:29after just being shown a few examples.

43:33So I think if it's actually capable of doing that,

43:35that's novel, and that's very interesting,

43:37and that's something we should investigate.

43:39That said, I must say, I'm not entirely convinced

43:43that we have shown it's capable of doing that.

43:47It's very likely, given the amount of data

43:51that the model is trained on,

43:52that what it's actually doing is pattern matching

43:55a new task you give it with a task

43:58that it's been exposed to in its training data.

44:00It's just recognizing the task

44:01instead of just developing a model of the task, right?

44:05- But there's, sorry to interrupt,

44:07there's parallels to what you said before,

44:10which is it's possible to see GPT-3

44:13as like the prompts it's given

44:15as a kind of SQL query into this thing that it's learned,

44:19similar to what you said before,

44:20which is language is used to query the memory.

44:23- Yes.

44:24- So is it possible that neural network

44:26is a giant memorization thing,

44:29but then if it gets sufficiently giant,

44:32it'll memorize sufficiently large amounts

44:35of things in the world,

44:36or it becomes, or intelligence becomes a querying machine?

44:40- I think it's possible that a significant chunk

44:44of intelligence is this giant associative memory.

44:47I definitely don't believe that intelligence

44:51is just a giant associative memory,

44:53but it may well be a big component.

44:57- So do you think GPT-3, four, five,

45:02GPT-10 will eventually,

45:05like, what do you think, where's the ceiling?

45:08Do you think you'll be able to reason?

45:10No, that's a bad question.

45:13Like, what is the ceiling is the better question.

45:17- How well is it gonna scale?

45:18How good is GPT-N going to be?

45:21- Yeah.

45:22- So I believe GPT-N is gonna--

45:25- GPT-N?

45:26- Is gonna improve on the strength of GPT-2 and 3,

45:30which is it will be able to generate, you know,

45:34ever more plausible text in context.

45:37- Just monotonically increasing performance.

45:39- Yes, if you train a bigger model on more data,

45:44then your text will be increasingly more context aware

45:49and increasingly more plausible,

45:51in the same way that GPT-3 is much better

45:54at generating plausible text compared to GPT-2.

45:57But that said, I don't think just scaling up the model

46:03to more transformer layers and more trained data

46:05is gonna address the flaws of GPT-3,

46:08which is that it can generate plausible text,

46:11but that text is not constrained by anything else

46:15other than plausibility.

46:16So in particular, it's not constrained by factualness

46:20or even consistency,

46:22which is why it's very easy to get GPT-3

46:24to generate statements that are factually untrue

46:27or to generate statements that are even self-contradictory,

46:31right?

46:32Because its only goal is plausibility

46:36and it has no other constraints.

46:39It's not constrained to be self-consistent, for instance.

46:42And so for this reason,

46:44one thing that I thought was very interesting with GPT-3

46:46is that you can pre-determine the answer it will give you

46:51by asking the question in a specific way,

46:53because it's very responsive to the way you ask the question

46:56since it has no understanding of the content of the question.

47:01And if you ask the same question in two different ways

47:07that are basically adversarially engineered

47:10to produce certain answer,

47:11you will get two different answers,

47:14two contradictory answers.

§06Transcript · 47:15–56:40

47:15- It's very susceptible to adversarial attacks, essentially.

47:18- Potentially, yes.

47:19So in general, the problem with these models,

47:22these generative models is that

47:24they're very good at generating plausible text,

47:27but that's just not enough, right?

47:30I think one avenue that would be very interesting

47:36to make progress is to make it possible

47:39to write programs over the latent space

47:43that these models operate on,

47:45that you would rely on these self-supervised models

47:49to generate a sort of pool of knowledge and concepts

47:54and common sense,

47:55and then you would be able to write explicit

47:58reasoning programs over it.

48:01Because the current problem with GPT-3

48:03is that it can be quite difficult to get it

48:06to do what you want to do.

48:09If you want to turn GPT-3 into products,

48:12you need to put constraints on it.

48:14You need to force it to obey certain rules.

48:19So you need a way to program it explicitly.

48:22- Yeah, so if you look at its ability

48:24to do program synthesis,

48:26it generates, like you said, something that's plausible.

48:29- Yeah, so if you try to make it generate programs,

48:32it will perform well for any program

48:35that it has seen in its training data,

48:38but because program space is not interpretative, right?

48:44It's not gonna be able to generalize to problems

48:46it hasn't seen before.

48:48- Now that's currently, do you think,

48:51sort of an absurd, but I think useful,

48:56I guess, intuition builder is,

48:59you know, the GPT-3 has 175 billion parameters.

49:05The human brain has 100,

49:09has about a thousand times that or more

49:13in terms of number of synapses.

49:14Do you think, obviously, very different kinds of things,

49:21but there is some degree of similarity.

49:26Do you think, what do you think GPT will look like

49:30when it has 100 trillion parameters?

49:34You think our conversation might be in nature different?

49:38'Cause you've criticized GPT-3 very effectively now.

49:43Do you think?

49:43- No, I don't think so.

49:46So to begin with the bottleneck with scaling up GPT-3,

49:51GPT models, generative pre-trained transformer models,

49:54is not gonna be the size of the model

49:57or how long it takes to train it.

49:59The bottleneck is gonna be the trained data

50:01because OpenAI is already training GPT-3

50:05on a crawl of basically the entire web, right?

50:08And that's a lot of data.

50:09So you could imagine training on more data than that.

50:12Google could train on more data than that,

50:14but it would still be only incrementally more data.

50:17And I don't recall exactly how much more data

50:20GPT-3 was trained on compared to GPT-2,

50:22but it's probably at least like 100,

50:25or maybe even a thousand X.

50:26Don't have the exact number.

50:28You're not gonna be able to train a model

50:30on a hundred more data than what you're already doing.

50:34- So that's brilliant.

50:35So it's not, you know,

50:36it's easier to think of compute as a bottleneck

50:38and then arguing that we can remove that bottleneck, but-

50:41- We can remove the compute bottleneck.

50:43I don't think it's a big problem.

50:44If you look at the pace at which we've improved

50:48the efficiency of deep learning models

50:50in the past few years,

50:53I'm not worried about train time bottlenecks

50:57or model size bottlenecks.

50:58The bottleneck in the case of these

51:02generative transformer models

51:03is absolutely the trained data.

51:05- What about the quality of the data?

51:07So- - So, yeah.

51:08So the quality of the data is an interesting point.

51:10The thing is, if you're gonna want to use these models

51:14in real products,

51:15then you want to feed them data

51:20that's as high quality as factual,

51:23I would say as unbiased as possible,

51:25but you know, there's not really such a thing

51:27as unbiased data in the first place.

51:30But you probably don't want to train it on Reddit,

51:34for instance.

51:34It sounds like a bad plan.

51:37So from my personal experience working with

51:40large scale deep learning models,

51:42so at some point I was working on a model at Google

51:46that's trained on like 350 million labeled images.

51:51It's an image classification model.

51:53That's a lot of images.

51:54That's like probably most publicly available images

51:58on the web at the time.

51:59And it was a very noisy dataset

52:03because the labels were not originally annotated by hand,

52:07by humans.

52:08They were automatically derived from like tags

52:12on social media or just keywords in the same page

52:16as the image was found and so on.

52:18So it was very noisy.

52:19And it turned out that you could easily get a better model,

52:24not just by training,

52:26like if you train on more of the noisy data,

52:29you get an incrementally better model,

52:31but you very quickly hit diminishing returns.

52:35On the other hand,

52:36if you train on smaller dataset

52:38with higher quality annotations,

52:39annotations that are actually made by humans,

52:44you get a better model.

52:47And it also takes less time to train it.

52:50- Yeah, that's fascinating.

52:51It's the self-supervised learning.

52:53There's a way to get better doing the automated labeling.

52:58- Yeah, so you can enrich or refine your labels

53:03in an automated way.

53:05- That's correct.

53:07- Do you have a hope for,

53:08I don't know if you're familiar

53:09with the idea of a semantic web.

53:11Is a semantic web,

53:13just for people who are not familiar,

53:15and is the idea of being able to convert the internet

53:20or be able to attach like semantic meaning

53:25to the words on the internet,

53:27the sentences, the paragraphs,

53:29to be able to convert information on the internet

53:33or some fraction of the internet

53:35into something that's interpretable by machines.

53:38That was kind of a dream for,

53:43I think the semantic web papers in the 90s.

53:47It's kind of the dream that,

53:49the internet is full of rich, exciting information.

53:52Even just looking at Wikipedia,

53:54we should be able to use that as data for machines.

53:57And so far-- - The information

53:59is not really in a format that's available to machines.

54:01So no, I don't think the semantic web will ever work

54:04simply because it would be a lot of work, right?

54:08To make, to provide that information in structured form.

54:12And there is not really any incentive

54:13for anyone to provide that work.

54:16So I think the way forward to make the knowledge

54:21on the web available to machines

54:22is actually something closer to unsupervised deep learning.

54:26- Yeah. - The GPT-3

54:30is actually a bigger step in the direction

54:32of making the knowledge of the web available to machines

54:34than the semantic web was.

54:36- Yeah, perhaps in a human centric sense,

54:40it feels like GPT-3 hasn't learned anything

54:45that could be used to reason.

54:49But that might be just the early days.

54:52- Yeah, I think that's correct.

54:54I think the forms of reasoning that you see perform

54:57are basically just reproducing patterns

55:00that it has seen in the string data.

55:02So of course, if you're trained on the entire web,

55:06then you can produce an illusion of reasoning

55:09in many different situations,

55:10but it will break down if it's presented

55:13with a novel situation.

55:15- That's the open question between the illusion of reasoning

55:17and actual reasoning, yeah.

55:18- Yes, the power to adapt to something

55:21that is genuinely new.

55:22Because the thing is, even imagine you had,

55:28you could train on every bit of data ever generated

55:32in this tree of humanity.

55:34It remains, that model would be capable

55:38of anticipating many different possible situations,

55:43but it remains that the future

55:45is gonna be something different.

55:47Like for instance, if you train a GPT-3 model

55:51on data from the year 2002, for instance,

55:55and then use it today,

55:56it's gonna be missing many things.

55:58It's gonna be missing many common sense facts

56:01about the world.

56:02It's even gonna be missing vocabulary and so on.

56:05- Yeah, it's interesting that GPT-3 even doesn't have,

56:09I think, any information about the coronavirus.

56:13- Yes.

56:15Which is why a system that's,

56:17you tell that the system is intelligent

56:21when it's capable to adapt.

56:22So intelligence is gonna require

56:25some amount of continuous learning.

56:28It's also gonna require some amount of improvisation.

56:30Like it's not enough to assume that

56:33what you're gonna be asked to do

56:36is something that you've seen before,

56:38or something that is a simple interpolation

56:40of things you've seen before.

§07Transcript · 56:42–1:06:24

56:42- Yeah.

56:43- In fact, that model breaks down for,

56:45even very tasks that look relatively simple

56:51from a distance, like L5 self-driving, for instance.

56:55Google had a paper a couple of years back

56:59showing that something like 30 million

57:03different road situations

57:05were actually completely insufficient

57:07to train a driving model.

57:09It wasn't even L2, right?

57:11And that's a lot of data.

57:12That's a lot more data than the 20 or 30 hours of driving

57:16that a human needs to learn to drive,

57:19given the knowledge they've already accumulated.

57:21- Well, let me ask you on that topic.

57:24Elon Musk, Tesla Autopilot,

57:29one of the only companies I believe

57:31is really pushing for a learning-based approach.

57:34Are you skeptical that that kind of network

57:37can achieve level four?

57:38- L4 is probably achievable.

57:42L5 probably not.

57:44- What's the distinction there?

57:45Is L5 is completely, you can just fall asleep?

57:49- Yeah, L5 is basically human level.

57:51Well, driving, I have to be careful saying human level

57:53'cause like that's the most--

57:54- Yeah, there are tons of drivers.

57:56- Yeah, that's the clearest example of like,

57:59you know, cars will most likely be much safer than humans

58:03in many situations where humans fail.

58:06It's the vice versa question.

58:08- So I'll tell you, you know,

58:11the thing is the amounts of trained data you would need

58:14to anticipate for pretty much every possible situation

58:17you'll encounter in the real world

58:20is such that it's not entirely unrealistic

58:23to think that at some point in the future

58:25we'll develop a system that's trained on enough data,

58:27especially provided that we can simulate

58:31a lot of that data.

58:32We don't necessarily need actual cars on the road

58:35for everything, but it's a massive effort.

58:39And it turns out you can create a system

58:41that's much more adaptive,

58:43that can generalize much better

58:45if you just add explicit models

58:51of the surroundings of the car.

58:53And if you use deep learning for what it's good at,

58:55which is to provide perceptive information.

58:59So in general, deep learning is a way to encode perception

59:03and a way to encode intuition,

59:05but it is not a good medium

59:07for any sort of explicit reasoning.

59:11And in AI systems today,

59:14strong generalization tends to come from explicit models,

59:20tend to come from abstractions in the human mind

59:24that are encoded in program form by a human engineer.

59:28These are the abstractions you can actually generalize,

59:31not the sort of weak abstraction

59:33that is learned by a neural network.

59:34- Yeah, and the question is how much reasoning,

59:38how much strong abstractions are required

59:41to solve particular tasks like driving?

59:44That's the question, or human life, existence.

59:48How much strong abstractions does existence require,

59:53but more specifically on driving?

59:55That seems to be a coupled question about intelligence

60:00is like how much intelligence,

60:04like how do you build an intelligent system?

60:07And the coupled problem, how hard is this problem?

60:11How much intelligence does this problem actually require?

60:14So we get to cheat, right?

60:18'Cause we get to look at the problem.

60:19It's not like you get to close our eyes

60:22and completely new to driving.

60:24We get to do what we do as human beings,

60:26which is for the majority of our life,

60:30before we ever learn, quote unquote, to drive,

60:32we get to watch other cars and other people drive.

60:35We get to be in cars, we get to watch,

60:37we get to see movies about cars,

60:39we get to observe all this stuff.

60:42And that's similar to what neural networks are doing,

60:45is getting a lot of data

60:47and the question is, yeah,

60:51how many leaps of reasoning genius is required

60:56to be able to actually effectively drive?

60:59- I think it's for example of driving.

61:01I mean, sure, you've seen a lot of cars in your life

61:06before you learn to drive,

61:07but let's say you've learned to drive in Silicon Valley

61:10and now you rent a car in Tokyo.

61:14Well, now everyone is driving on the other side of the road

61:16and the signs are different

61:18and the roads are more narrow and so on.

61:20So it's a very, very different environment

61:22and a smart human, even an average human,

61:26should be able to just zero shot it,

61:29to just be operational in this very different environment

61:34right away, despite having had no contact

61:38with the novel complexity

61:41that is contained in this environment, right?

61:44And that is novel complexity,

61:45it's not just interpolation over the situations

61:50that you've encountered previously,

61:52like learning to drive in the US, right?

61:55- I would say the reason I ask

61:56is one of the most interesting tests of intelligence

61:59we have today actively, which is driving,

62:03in terms of having an impact on the world.

62:06Like when do you think we'll pass

62:08that test of intelligence?

62:09- So I don't think driving is that much of a test

62:12of intelligence because again,

62:14there is no task for which skill at that task

62:18demonstrates intelligence,

62:20unless it's a kind of meta task

62:23that involves acquiring new skills.

62:26So I don't think, I think you can actually solve driving

62:29without having any real amount of intelligence.

62:34For instance, if you really did have infinite training data,

62:38you could just literally train

62:41an end-to-end deep learning model that does driving,

62:44provided infinite training data.

62:45The only problem with the whole idea

62:49is collecting a data sets that's sufficiently comprehensive

62:53that covers the very long tail

62:55of possible situations you might encounter.

62:57And it's really just a scale problem.

62:59So I think there's nothing fundamentally wrong

63:03with this plan, with this idea.

63:06It's just that it strikes me

63:09as a fairly inefficient thing to do

63:11because you run into this scaling issue

63:16with diminishing returns.

63:17Whereas if instead you took a more manual engineering

63:21approach where you use deep learning modules

63:26in combination with engineering an explicit model

63:32of the surrounding of the cars

63:33and you bridge the two in a clever way,

63:36your model will actually start generalizing much earlier

63:39and more effectively than the end-to-end deep learning model.

63:42So why would you not go

63:44with the more manual engineering oriented approach?

63:47Like even if you created that system,

63:50either the end-to-end deep learning model system

63:52that's running on infinite data

63:53or the slightly more human system,

63:58I don't think achieving L5 would demonstrate

64:01general intelligence or intelligence of any generality at all.

64:05Again, the only possible test of generality in AI

64:10would be a test that looks at skill acquisition

64:12over unknown tasks.

64:14But for instance, you could take your L5 driver

64:17and ask it to learn to pilot a commercial airplane

64:21for instance, and then you would look at

64:23how much human involvement is required

64:25and how much training data is required

64:28for the system to learn to pilot an airplane.

64:29And that gives you a measure

64:33of how intelligent that system really is.

64:35- Yeah, well, I mean, that's a big leap.

64:37I get you, but I'm more interested as a problem.

64:42I would see, to me, driving is a black box

64:46that can generate novel situations at some rate,

64:50like what people call edge cases.

64:53So it does have newness that keeps being,

64:56like we're confronted, let's say once a month.

64:59- It is a very long tail, yes.

65:01- It's a long tail.

65:01- But it doesn't mean you cannot solve it

65:03just by training a statistical model on a lot of data.

65:08- Huge amount of data.

65:09- It's really a matter of scale.

65:12- But I guess what I'm saying is,

65:14if you have a vehicle that achieves level five,

65:17it is going to be able to deal with new situations.

65:22Or, I mean, the data is so large

65:28that the rate of new situations is very low.

65:32- Yes.

65:33- That's not intelligence.

65:34So if we go back to your kind of definition of intelligence,

65:37it's the efficiency.

65:39- With which you can adapt to new situations,

65:42to truly new situations,

65:43not situations you've seen before, right?

65:45Not situations that could be anticipated by your creators,

65:48by the creators of the system, but truly new situations.

65:51The efficiency with which you acquire new skills.

65:55If you require, if in order to pick up a new skill,

65:58you require a very extensive training data set

66:03of most possible situations that can occur

66:07in the practice of that skill,

66:09then the system is not intelligent.

66:10It is mostly just a lookup table.

66:13- Yeah, well.

66:16- Likewise, if in order to acquire a skill,

66:20you need a human engineer to write down a bunch of rules

66:24that cover most or every possible situation.

§08Transcript · 1:06:27–1:16:15

66:27Likewise, the system is not intelligent.

66:29The system is merely the output artifact

66:32of a process that happens in the minds

66:37of the engineers that are creating it, right?

66:41It is encoding an abstraction

66:44that's produced by the human mind.

66:46And intelligence would actually be

66:48the process of producing,

66:53of autonomously producing this abstraction.

66:56- Yeah.

66:57- Not like, if you take an abstraction

66:59and you encode it on a piece of paper

67:01or in a computer program,

67:03the abstraction itself is not intelligent.

67:06What's intelligent is the agent

67:09that's capable of producing these abstractions, right?

67:11- Yeah, it feels like there's a little bit of a gray area.

67:15Like, 'cause you're basically saying

67:17that deep learning forms abstractions too,

67:20but those abstractions do not seem to be effective

67:25for generalizing far outside of the things

67:29that it's already seen.

67:30But generalize a little bit.

67:31- Yeah, absolutely.

67:32No, deep learning does generalize a little bit.

67:34Like, generalization is not binary, it's more like a spectrum.

67:38- Yeah, and there's a certain point,

67:40it's a gray area, but there's a certain point

67:42where there's an impressive degree

67:43of generalization that happens.

67:46No, like, I guess exactly what you were saying is

67:52intelligence is how efficiently you're able to generalize

67:57far outside of the distribution

68:01of things you've seen already.

68:03- Yes.

68:04- So it's both like the distance of how far you can,

68:06like how new, how radically new something is

68:10and how efficiently you're able to deal with that.

68:12- So you can think of intelligence as a measure

68:16of an information conversion ratio.

68:18Like imagine a space of possible situations

68:22and you've covered some of them.

68:27So you have some amount of information

68:29about your space of possible situations.

68:32That's provided by the situations you already know.

68:34And that's on the other hand,

68:35also provided by the prior knowledge

68:38that the system brings to the table,

68:41the prior knowledge that's embedded in the system.

68:43So the system starts with some information, right,

68:46about the problem, about the task.

68:48And it's about going from that information to a program,

68:53what we would call a skill program, a behavioral program

68:56that can cover a large area of possible situation space.

69:00And essentially the ratio between that area

69:04and the amount of information you start with is intelligence.

69:07So a very smart agent can make efficient uses

69:14of very little information about a new problem

69:17and very little prior knowledge as well

69:19to cover a very large area of potential situations

69:23in that problem without knowing

69:26what these future new situations are going to be.

69:29- So one of the other big things you talk about in the paper,

69:34we've talked about a little bit already,

69:36but let's talk about it some more,

69:37is the actual tests of intelligence.

69:40So if we look at like human and machine intelligence,

69:45do you think tests of intelligence should be different

69:49for humans and machines,

69:50or how we think about testing of intelligence?

69:53Are these fundamentally the same kind of intelligences

69:58that we're after and therefore the tests should be similar?

70:03- So if your goal is to create AIs

70:07that are more human-like,

70:10then it will be super valuable, obviously,

70:12to have a test that's universal,

70:15that applies to both AIs and humans,

70:19so that you could establish a comparison

70:22between the two that you could tell exactly

70:25how intelligent, in terms of human intelligence,

70:29a given system is.

70:30So that said, the constraints

70:34that apply to artificial intelligence

70:36and to human intelligence are very different,

70:39and your tests should account for this difference.

70:43Because if you look at artificial systems,

70:47it's always possible for an experimenter

70:50to buy arbitrary levels of skill at arbitrary tasks,

70:55either by injecting hard-coded prior knowledge

71:00into the system via rules and so on

71:05that come from the human mind,

71:06from the minds of the programmers,

71:08and also buying higher levels of skill

71:13just by training on more data.

71:15For instance, you could generate

71:16an infinity of different Go games,

71:19and you could train a Go playing system that way,

71:23but you could not directly compare it

71:26to human Go playing skills,

71:28because a human that plays Go had to develop that skill

71:32in a very constrained environment.

71:34They had a limited amount of time,

71:36they had a limited amount of energy,

71:38and of course, this started from a different set of priors.

71:42This started from innate human priors.

71:47So I think if you want to compare

71:49the intelligence of two systems,

71:51like the intelligence of an AI

71:53and the intelligence of a human,

71:56you have to control for priors.

71:59You have to start from the same set of knowledge priors

72:04about the task, and you have to control for experience,

72:08that is to say for training data.

72:11- So what's priors?

72:15- So prior is whatever information you have

72:18about a given task before you start learning

72:21about this task.

72:23- And how's that different from experience?

72:25- Well, experience is acquired, right?

72:28So for instance, if you're trying to play Go,

72:31your experience with Go is all the Go games

72:33you've played or you've seen,

72:36or you've simulated in your mind, let's say.

72:38And your priors are things like,

72:42well, Go is a game on the 2D grid,

72:46and we have lots of hard-coded priors

72:48about the organization of 2D space.

72:53- And so rules of how the dynamics of this,

72:57the physics of this game in this 2D space.

73:00- Yes.

73:01- The idea that you have, what winning is.

73:04- Yes, exactly.

73:05And other board games can also show some similarity with Go.

73:09And if you've played these board games,

73:11then with respect to the game of Go,

73:13that would be part of your priors about the game.

73:16- Well, it's interesting to think about the game of Go

73:18is how many priors are actually brought to the table.

73:21When you look at self-play, reinforcement learning-based

73:27mechanisms that do learning,

73:28it seems like the number of priors is pretty low.

73:31- Yes.

73:31- But you're saying you should be-

73:32- There is a 2D spatial priors in the covenant.

73:35- Right.

73:36But you should be clear at making those priors explicit.

73:40- Yes.

73:41So in particular, I think if your goal

73:44is to measure a human-like form of intelligence,

73:47then you should clearly establish

73:49that you want the AI you're testing

73:52to start from the same set of priors that humans start with.

73:57- Right.

73:58So, I mean, to me personally,

74:01but I think to a lot of people,

74:02the human side of things is very interesting.

74:05So testing intelligence for humans.

74:08What do you think is a good test of human intelligence?

74:12- Well, that's the question that psychometrics

74:17is interested in.

74:19- What's-

74:20- That's an entire subfield of psychology

74:22that deals with this question.

74:23- So what's psychometrics?

74:25- The psychometrics is the subfield of psychology

74:28that tries to measure, quantify aspects of the human mind.

74:33So in particular, cognitive abilities, intelligence,

74:37and personality traits as well.

74:39- So, like what are, might be a weird question,

74:43but what are like the first principles

74:45of psychometrics that operates on, you know,

74:52what are the priors it brings to the table?

74:55- So it's a field with a fairly long history.

74:58It's, so, you know, psychology sometimes gets

75:03a bad reputation for not having very reproducible results.

75:08And so psychometrics has actually some

75:11fairly solidly reproducible results.

75:14So the ideal goals of the field is, you know,

75:17a test should be reliable,

75:20which is a notion tied to reproducibility.

75:23It should be valid, meaning that it should actually

75:26measure what you say it measures.

75:29So for instance, if you're saying

75:32that you're measuring intelligence,

75:34then your test results should be correlated

75:36with things that you expect to be correlated

75:39with intelligence, like success in school,

75:41or success in the workplace, and so on.

75:43Should be standardized, meaning that you can administer

75:47your tests to many different people in some conditions.

75:50And it should be free from bias,

75:52meaning that, for instance, if your test involves

75:57the English language, then you have to be aware

75:59that this creates a bias against people

76:02who have English as their second language,

76:04or people who can't speak English at all.

76:07So of course, these principles

76:09for creating psychometric tests are very much an ideal.

76:13I don't think every psychometric test

76:15is really either reliable,

§09Transcript · 1:16:18–1:25:35

76:18valid, or free from bias.

76:22But at least the field is aware of these weaknesses,

76:25and is trying to address them.

76:27- So it's kind of interesting.

76:28Ultimately, you're only able to measure,

76:31like you said previously, the skill.

76:34But you're trying to do a bunch of measures

76:36of different skills that correlate,

76:38as you mentioned, strongly with some general concept

76:41of cognitive ability.

76:43- Yes, yes.

76:44- So what's the G factor?

76:46- So, right, there are many different kinds

76:48of tests of intelligence.

76:50And each of them is interested

76:53in different aspects of intelligence.

76:56Some of them will deal with language,

76:57some of them will deal with spatial vision,

77:01maybe mental rotations, numbers, and so on.

77:04When you run these very different tests at scale,

77:08what you start seeing is that there are clusters

77:11of correlations among test results.

77:14So for instance, if you look at homework at school,

77:19you will see that people who do well at math

77:21are also likely, statistically, to do well in physics.

77:25And what's more, there are also people who do well at math,

77:29and physics are also statistically likely

77:32to do well in things that sound completely unrelated,

77:35like writing an English essay, for instance.

77:38And so when you see clusters of correlations

77:41in statistical terms, you would explain them

77:46with a latent variable.

77:47And the latent variable that would, for instance,

77:49explain the relationship between being good at math

77:53and being good at physics would be cognitive ability.

77:56And the G factor is the latent variable

78:00that explains the fact that every test of intelligence

78:05that you can come up with results on this test

78:09and they're being correlated.

78:10So there is some single, unique variable

78:16that explains these correlations, that's the G factor.

78:18So it's a statistical construct.

78:20It's not really something you can directly measure,

78:23for instance, in a person.

78:25- But it's there.

78:26- But it's there, it's there, it's there at scale.

78:28And that's also one thing I want to mention

78:31about psychometrics.

78:33Like, you know, when you talk about measuring intelligence

78:36in humans, for instance, some people get a little bit worried

78:40they will say, you know, that sounds dangerous,

78:41maybe that sounds potentially discriminatory and so on.

78:44And they're not wrong.

78:46And the thing is, so personally,

78:48I'm not interested in psychometrics

78:50as a way to characterize one individual person.

78:54Like if I get your psychometric personality assessments

78:59or your IQ, I don't think that actually tells me much

79:03about you as a person.

79:05I think psychometrics is most useful as a statistical tool.

79:10So it's most useful at scale.

79:12It's most useful when you start getting test results

79:15for a large number of people

79:17and you start cross correlating these test results

79:20because that gives you information about the structure

79:25of the human mind,

79:26in particular about the structure

79:28of human cognitive abilities.

79:29So at scale, psychometrics paints a certain picture

79:34of the human mind, and that's interesting.

79:37And that's what's relevant to AI,

79:39the structure of human cognitive abilities.

79:41- Yeah, it gives you an insight into,

79:42I mean, to me, I remember when I learned about g-factor,

79:45it seemed like it would be impossible for it to be real,

79:50even as a statistical variable.

79:55Like it felt kind of like astrology.

79:59Like it's like wishful thinking among psychologists.

80:02But the more I learned, I realized that there's some,

80:05I mean, I'm not sure what to make about human beings,

80:07the fact that the g-factor is a thing.

80:10That there's a commonality across all of the human species,

80:13that there does need to be a strong correlation

80:15between cognitive abilities.

80:17That's kind of fascinating.

80:18- Yeah, so human cognitive abilities have a structure,

80:22like the most mainstream theory of the structure

80:25of cognitive abilities is called a CHC theory.

80:28So Cattle, Horn, Carroll,

80:30it's named after the three psychologists

80:32who contributed key pieces of it.

80:35And it describes cognitive abilities as a hierarchy

80:40with three levels.

80:41And at the top, you have the g-factor,

80:43then you have broad cognitive abilities,

80:46for instance, fluid intelligence, right?

80:48That encompass a broad set of possible kinds of tasks

80:53that are all related.

80:57And then you have narrow cognitive abilities

80:59at the last level, which is closer to task specific skill.

81:04And there are actually different theories

81:08of the structure of cognitive abilities

81:10that just emerged from different statistical analysis

81:12of IQ test results.

81:14But they all describe a hierarchy

81:17with a kind of g-factor at the top.

81:21And you're right that the g-factor is,

81:23it's not quite real in the sense

81:25that it's not something you can observe and measure,

81:29like your height, for instance.

81:30But it's really in the sense that you see it

81:33in a statistical analysis of the data, right?

81:37One thing I want to mention is that

81:39the fact that there is a g-factor

81:40does not really mean that human intelligence

81:43is a general in a strong sense.

81:45Does not mean human intelligence

81:47can be applied to any problem at all.

81:50And that someone who has a high IQ

81:52is gonna be able to solve any problem at all.

81:54That's not quite what it means.

81:55I think one popular analogy to understand it

82:00is the sports analogy.

82:03If you consider the concept of physical fitness,

82:06it's a concept that's very similar to intelligence

82:09because it's a useful concept.

82:11It's something you can intuitively understand.

82:14Some people are fit, maybe like you.

82:17Some people are not as fit, maybe like me.

82:20- But none of us can fly.

82:21- Absolutely.

82:23- It's a constraint to a specific set of skills.

82:25- Even if you're very fit,

82:26that doesn't mean you can do anything at all

82:29in any environment.

82:31You obviously cannot fly.

82:32You cannot surf over the bottom of the ocean and so on.

82:36And if you were a scientist

82:37and you wanted to precisely define

82:40and measure physical fitness in humans,

82:43then you would come up with a battery of tests.

82:47Like you would have running 100 meter,

82:50playing soccer, playing table tennis, swimming, and so on.

82:54And if you run these tests over many different people,

82:58you would start seeing correlations in test results.

83:01For instance, people who are good at soccer

83:03are also good at sprinting.

83:05And you would explain these correlations

83:08with physical abilities

83:10that are strictly analogous to cognitive abilities.

83:14And then you would start also observing correlations

83:17between biological characteristics,

83:21like maybe lung volume is correlated

83:23with being a fast runner, for instance.

83:27And in the same way that there are neurophysical correlates

83:31of cognitive abilities.

83:34And at the top of the hierarchy of physical abilities

83:38that you would be able to observe,

83:39you would have a G factor, a physical G factor,

83:43which would map to physical fitness.

83:45And as you just said,

83:47that doesn't mean that people

83:49with high physical fitness can fly.

83:51It doesn't mean human morphology

83:53and human physiology is universal.

83:55It's actually super specialized.

83:57We can only do the things that we were evolved to do.

84:03Like we are not appropriate to...

84:05You could not exist on Venus or Mars

84:09or in the void of space or the bottom of the ocean.

84:12So that said, one thing that's really striking

84:15and remarkable is that our morphology

84:20generalizes far beyond the environments that we evolved for.

84:27Like in a way you could say we evolved

84:29to run after prey in the savannah, right?

84:32That's very much where our human morphology comes from.

84:36And that said, we can do a lot of things

84:40that are completely unrelated to that.

84:42We can climb mountains, we can swim across lakes,

84:47we can play table tennis.

84:49I mean, table tennis is very different

84:50from what we were evolved to do, right?

84:53So our morphology, our bodies,

84:55our sense of motor affordances

84:57are of a degree of generality

84:59that is absolutely remarkable, right?

85:02And I think cognition is very similar to that.

85:05Our cognitive abilities have a degree of generality

85:08that goes far beyond what the mind

85:10was initially supposed to do,

85:12which is why we can play music and write novels

85:15and go to Mars and do all kinds of crazy things.

85:18But it's not universal in the same way

85:20that human morphology and our body

85:23is not appropriate for actually most

85:26of the universe by volume.

85:27In the same way you could say that the human mind

85:29is not really appropriate for most of problem space,

85:32potential problem space by volume.

85:35So we have very strong cognitive biases, actually,

§10Transcript · 1:25:39–1:35:08

85:39that mean that there are certain types of problems

85:42that we handle very well,

85:43and certain types of problem

85:45that we are completely inadaptive for.

85:48So that's really how we'd interpret the G-factor.

85:52It's not a sign of strong generality.

85:56It's really just the broadest cognitive ability.

86:00But our abilities,

86:02whether we are talking about sensory motor abilities

86:05or cognitive abilities,

86:06they still remain very specialized

86:09in the human condition, right?

86:11- Within the constraints of the human cognition,

86:16they're general. (laughs)

86:18- Yes, absolutely.

86:19- But the constraints, as you're saying, are very limited.

86:21- What's, I think what's, yeah.

86:23- Limiting.

86:23So we evolved our cognition and our body,

86:27evolved in very specific environments.

86:29Because our environment was so variable,

86:31fast-changing, and so unpredictable,

86:34part of the constraints that drove our evolution

86:37is generality itself.

86:39So we were, in a way, evolved to be able to improvise

86:42in all kinds of physical or cognitive environments, right?

86:46- Yeah.

86:47- And for this reason,

86:49it turns out that the minds and bodies

86:53that we ended up with

86:55can be applied to much, much broader scope

86:58than what they were evolved for, right?

87:00And that's truly remarkable.

87:01And that goes, that's a degree of generalization

87:03that is far beyond anything you can see

87:06in artificial systems today, right?

87:08That said, it does not mean that human intelligence

87:14is anywhere universal.

87:16- Yeah, it's not general.

87:17You know, it's a kind of exciting topic for people,

87:21even outside of artificial intelligence, is IQ tests.

87:24I think it's Mensa, whatever.

87:29There's different degrees of difficulty for questions.

87:32We talked about this offline a little bit, too,

87:34about sort of difficult questions.

87:37You know, what makes a question on an IQ test

87:40more difficult or less difficult, do you think?

87:43- So the thing to keep in mind is that

87:46there's no such thing as a question

87:49that's intrinsically difficult.

87:51It has to be difficult to suspect

87:53to the things you already know

87:55and the things you can already do, right?

87:58So in terms of an IQ test question,

88:02typically it would be structured, for instance,

88:05as a set of demonstration input and output pairs, right?

88:10And then you would be given a test input, a prompt,

88:15and you would need to recognize or produce

88:18the corresponding output.

88:20And in that narrow context,

88:23you could say a difficult question

88:25is a question where the input prompt

88:31is very surprising and unexpected,

88:34given the training examples.

88:36- Just even the nature of the patterns

88:38that you're observing in the input prompt.

88:40- For instance, let's say you have a rotation problem.

88:43You must rotate a shape by 90 degrees.

88:46If I give you two examples,

88:48and then I give you one prompt,

88:50which is actually one of the two training examples,

88:53then there is zero generalization difficulty for the task.

88:56It's actually a trivial task.

88:57You just recognize that it's one of the training examples

89:00and you probably use the same answer.

89:02Now, if it's a more complex shape,

89:05there is a little bit more generalization,

89:07but it remains that you are still doing the same thing

89:11at test time as you were being demonstrated

89:13at training time.

89:15A difficult task starts to require

89:17some amount of test time adaptation,

89:21some amount of improvisation.

89:25So consider, I don't know,

89:28you're teaching a class on quantum physics or something.

89:31If you wanted to test the understanding

89:39that students have of the material,

89:41you would come up with an exam

89:45that's very different from anything they've seen

89:48like on the internet when they were cramming.

89:51On the other hand, if you wanted to make it easy,

89:54you would just give them something

89:56that's very similar to the mock exams

90:00that they've taken,

90:02something that's just a simple interpolation

90:04of questions that they've already seen.

90:07And so that would be an easy exam.

90:09It's very similar to what you've been trained on.

90:12And a difficult exam is one

90:13that really probes your understanding

90:15because it forces you to improvise.

90:19It forces you to do things that are different

90:22from what you were exposed to before.

90:24So that said, it doesn't mean that the exam

90:28that requires improvisation is intrinsically hard, right?

90:32Because maybe you're a quantum physics expert.

90:35So when you take the exam,

90:37this is actually stuff that despite being new

90:39to the students, it's not new to you, right?

90:42So it can only be difficult with respect

90:46to what the test taker already knows

90:49and with respect to the information

90:51that the test taker has about the task.

90:54So that's what I mean by controlling for priors,

90:57what you, the information you bring to the table.

90:59- And the experience.

91:00- And the experience, which is the training data.

91:02So in the case of the quantum physics exam,

91:05that would be all the course material itself

91:09and all the mock exams that students might have taken online.

91:12- Yeah, it's interesting 'cause I've also,

91:15I sent you an email and asked you,

91:18like I've been, just this curious question of,

91:22you know, what's a really hard IQ test question.

91:27And I've been talking to also people

91:30who have designed IQ tests.

91:32There's a few folks on the internet.

91:33It's like a thing.

91:34People are really curious about it.

91:36First of all, most of the IQ tests they designed,

91:39they like religiously protect against the correct answers.

91:44Like you can't find the correct answers anywhere.

91:48In fact, the question is ruined once you know,

91:50even like the approach you're supposed to take.

91:53So they're very--

91:54- That's the approach is implicit in the training examples.

91:58So if you release the training examples, it's over.

92:00- Well--

92:02- Which is why in ARC, for instance,

92:05there is a test set that is private and no one has seen it.

92:09- No, for really tough IQ questions, it's not obvious.

92:13It's not because the ambiguity.

92:17Like it's, I mean, we'll have to look through them,

92:20but like some number sequences and so on,

92:22it's not completely clear.

92:25So like you can get a sense, but there's like some,

92:29you know, when you look at a number sequence, I don't know,

92:33like your Fibonacci number sequence,

92:37if you look at the first few numbers,

92:39that sequence could be completed in a lot of different ways.

92:43And, you know, some are, if you think deeply,

92:45are more correct than others.

92:46Like there's a kind of intuitive simplicity

92:51and elegance to the correct solution.

92:53- Yes, I am personally not a fan of ambiguity

92:56in test questions actually,

92:58but I think you can have difficulty

93:01without requiring ambiguity,

93:03simply by making the test require a lot of extrapolation

93:08over the training examples.

93:09- But the beautiful question is difficult,

93:13but gives away everything when you give the training example.

93:17- Basically, yes.

93:18Meaning that, so the tests I'm interested in creating

93:23are not necessarily difficult for humans

93:27because human intelligence is the benchmark.

93:31They're supposed to be difficult for machines

93:34in ways that are easy for humans.

93:36Like I think an ideal test of human and machine intelligence

93:40is a test that is actionable,

93:44that highlights the need for progress,

93:48and that highlights the direction

93:50in which you should be making progress.

93:51- I think we'll talk about the ARC challenge

93:54and the test you've constructed,

93:55and you have these elegant examples.

93:58I think that highlight,

93:59this is really easy for us humans,

94:01but it's really hard for machines.

94:04But on the designing an IQ test

94:08for IQs of higher than 160 and so on,

94:13you have to say, you have to take that

94:15and put it on steroids, right?

94:16You have to think like, what is hard for humans?

94:19And that's a fascinating exercise in itself, I think.

94:23And it was an interesting question

94:27of what it takes to create a really hard question

94:31for humans because you again have to do the same process

94:36as you mentioned, which is something basically

94:41where the experience that you have likely

94:45to have encountered throughout your whole life,

94:48even if you've prepared for IQ tests,

94:51which is a big challenge,

94:53that this will still be novel for you.

94:55- Yeah, I mean, novelty is a requirement.

94:57You should not be able to practice for the questions

95:02that you're gonna be tested on, that's important.

95:04Because otherwise what you're doing

95:06is not exhibiting intelligence.

95:08What you're doing is just retrieving

§11Transcript · 1:35:10–1:45:51

95:10what you've been exposed before.

95:12It's the same thing as a deep learning model.

95:14If you train a deep learning model

95:15on all the possible answers, then it will ace your test.

95:20In the same way that a stupid student

95:26can still ace the test if they cram for it,

95:30they memorize a hundred different possible mock exams

95:35and then they hope that the actual exam

95:37will be a very simple interpolation of the mock exams.

95:41And that student could just be a deep learning model

95:43at that point, but you can actually do that

95:45without any understanding of the material.

95:48And in fact, many students pass their exams

95:50in exactly this way.

95:52And if you want to avoid that,

95:53you need an exam that's unlike anything they've seen

95:56that really probes their understanding.

96:00- So how do we design an IQ test for machines?

96:05An intelligent test for machines?

96:08- All right, so in the paper,

96:09I outline a number of requirements

96:12that you expect of such a test.

96:14And in particular, we should start by acknowledging

96:19the priors that we expect to be required

96:23in order to perform the test.

96:25So we should be explicit about the priors, right?

96:28And if the goal is to compare machine intelligence

96:31and human intelligence,

96:32then we should assume a human cognitive priors, right?

96:37And secondly, we should make sure that we are testing

96:42for skill acquisition ability,

96:44skill acquisition efficiency in particular,

96:46and not for skill itself,

96:48meaning that every task featured in your test

96:52should be novel and should not be something

96:54that you can anticipate.

96:56So for instance, it should not be possible

96:58to brute force the space of possible questions, right?

97:02To pre-generate every possible question and answer.

97:06So it should be tasks that cannot be anticipated,

97:10not just by the system itself,

97:12but by the creators of the system, right?

97:16- Yeah, you know what's fascinating?

97:17I mean, one of my favorite aspects of the paper

97:20and the work you do with the ARC Challenge

97:22is the process of making priors explicit.

97:27Just even that act alone is a really powerful one

97:33of like, what are, it's a really powerful question

97:38to ask of us humans.

97:40What are the priors that we bring to the table?

97:42So the next step is like, once you have those priors,

97:46how do you use them to solve a novel task?

97:50But like, just even making the priors explicit

97:53is a really difficult and really powerful step.

97:56And that's like visually beautiful

97:59and conceptually, philosophically beautiful part

98:01of the work you did with,

98:03and I guess continue to do probably

98:06with the paper and the ARC Challenge.

98:08Can you talk about some of the priors

98:10that we're talking about here?

98:12- Yes, so a researcher that has done a lot of work

98:15on what exactly are the knowledge priors

98:19that are innate to humans is Elizabeth Spelke

98:24from Harvard.

98:25So she developed the core knowledge theory

98:30which outlines four different core knowledge systems.

98:35So systems of knowledge that we are basically

98:39either born with or that we are hardwired

98:43to acquire very early on in our development.

98:47And there's no strong distinction between the two.

98:52Like if you are primed to acquire

98:57as a certain type of knowledge in just a few weeks,

99:01you might as well just be born with it.

99:03It's just part of who you are.

99:06And so there are four different core knowledge systems.

99:09Like the first one is the notion of objectness

99:13and basic physics.

99:16Like you recognize that something that moves

99:20coherently for instance, is an object.

99:23So we intuitively, naturally, innately divide the world

99:28into objects based on this notion of coherence,

99:31physical coherence.

99:32And in terms of elementary physics,

99:34there's the fact that objects can bump against each other

99:41and the fact that they can occlude each other.

99:44So these are things that we are essentially born with

99:48or at least that we are going to be acquiring

99:50extremely early because we're really hardwired

99:54to acquire them.

99:55- So a bunch of points, pixels that move together.

100:00- Are objects.

100:01- Are partly the same object.

100:02- Yes.

100:03- I mean, that like, I don't smoke weed,

100:08but if I did, that's something I could sit like all night

100:13and just like think about.

100:14I remember when I first, in your paper, just objectness.

100:16I wasn't self-aware, I guess, of that particular prior

100:21that that's such a fascinating prior that like--

100:27- That's the most basic one, but actually--

100:30- Objectness, just identity.

100:32Just, yeah, objectness.

100:34I mean, it's very basic, I suppose, but it's so fundamental.

100:39- It is fundamental to human cognition.

100:41- Yeah.

100:42- And the second prior that's also fundamental is agentness,

100:46which is not a real world, but so agentness.

100:50The fact that some of these objects that you segment

100:55your environment into, some of these objects are agents.

100:59So what's an agent?

101:00It's basically it's an object that has goals.

101:04So for instance-- - That has what?

101:06- That has goals, that is capable of pursuing goals.

101:09So for instance, if you see two dots moving

101:13in a roughly synchronized fashion,

101:16you will intuitively infer that one of the dots

101:19is pursuing the other.

101:21So that one of the dots is, and one of the dots is an agent,

101:26and its goal is to avoid the other dot.

101:29And one of the dots, the other dot is also an agent,

101:32and its goal is to catch the first dot.

101:35Pelkey has shown that babies, as young as three months,

101:40identify agentness and goal-directedness

101:45in their environment.

101:46Another prior is basic geometry and topology,

101:51like the notion of distance,

101:53the ability to navigate in your environment and so on.

101:57This is something that is fundamentally hardwired

102:01into our brain.

102:02It's in fact backed by very specific neural mechanisms,

102:07like for instance, grid cells and plate cells.

102:10So it's something that's literally hard-coded

102:15at the neural level in our hippocampus.

102:19And the last prior would be the notion of numbers.

102:23Like numbers are not actually a cultural construct.

102:26We are intuitively, innately able to do some basic counting

102:31and to compare quantities.

102:34So it doesn't mean we can do arbitrary arithmetic.

102:37- Counting, the act of counting.

102:39- Counting, like counting one, two, three-ish,

102:42then maybe more than three.

102:44You can also compare quantities.

102:45If I give you three dots and five dots,

102:49you can tell the side with five dots has more dots.

102:53So this is actually an innate prior.

102:56So that said, the list may not be exhaustive.

103:00So Spelke is still pursuing

103:04the potential existence of new knowledge systems,

103:09for instance, knowledge systems

103:12that would deal with social relationships.

103:15- Yeah, yeah, I mean, and there could be-

103:19- Which is much less relevant

103:22to something like ARC or IQ test in general.

103:24- Right, there could be stuff that's,

103:27like you said, rotation, symmetry,

103:29is it really interesting?

103:31- It's very likely that there is,

103:33speaking about rotation, that there is in the brain,

103:37a hard-coded system that is capable of performing rotations.

103:40One famous experiment that people did in the,

103:45I don't remember which was exactly, but in the '70s,

103:51was that people found that if you asked people,

103:54if you give them two different shapes,

103:57and one of the shapes is a rotated version

104:01of the first shape, and you ask them,

104:03is that shape a rotated version of the first shape or not?

104:06What you see is that the time it takes people to answer

104:11is linearly proportional, right, to the angle of rotation.

104:16So it's almost like you have somewhere in your brain,

104:19like a turntable with a fixed speed,

104:24and if you want to know if two objects

104:26are rotated versions of each other,

104:29you put the object on the turntable,

104:31you let it move around a little bit,

104:34and then you stop when you have a match.

104:37And that's really interesting.

104:40- So what's the ARC challenge?

104:42- So in the paper I outlined, all these principles,

104:47that a good test of machine intelligence

104:50and human intelligence should follow.

104:51And the ARC challenge is one attempt

104:55to embody as many of these principles as possible.

104:58So I don't think it's anywhere near a perfect attempt,

105:02it does not actually follow every principle,

105:06but it is what I was able to do given the constraints.

105:10So the format of ARC is very similar to classic IQ tests,

105:15in particular Raven's Progressive Matrices.

105:18- Raven's?

105:19- Yeah, Raven's Progressive Matrices.

105:20I mean, if you've done IQ tests in the past,

105:22you know what it is probably, or at least you've seen it,

105:25even if you don't know what it's called.

105:27And so you have a set of tasks, that's what they're called,

105:32and for each task you have training data,

105:37which is a set of input and output pairs.

105:40So an input or output pair is a grid of colors, basically,

105:45the size of the grid is variable.

105:48The size of the grid is variable.

105:51And you're given an input and you must transform it

§12Transcript · 1:45:56–1:55:18

105:56into the proper output, right?

105:59And so you're shown a few demonstrations of a task

106:02in the form of existing input/output pairs,

106:05and then you're given a new input,

106:06and you must produce the correct output.

106:12And the assumptions in ARC is that

106:17every task should only require core knowledge priors,

106:25should not require any outside knowledge.

106:30So for instance, no language, no English, nothing like this,

106:35no concepts taken from our human experience,

106:41like trees, dogs, cats, and so on.

106:44So only reasoning tasks that are built

106:49on top of core knowledge priors.

106:52And some of the tasks are actually explicitly trying

106:56to probe specific forms of abstraction, right?

107:01Part of the reason why I wanted to create ARC

107:05is I'm a big believer in, you know,

107:11when you're faced with a problem as murky

107:16as understanding how to autonomously generate abstraction

107:20in a machine, you have to co-evolve the solution

107:25and the problem.

107:27And so part of the reason why I designed ARC

107:29was to clarify my ideas about the nature of abstraction,

107:33right?

107:34And some of the tasks are actually designed

107:36to probe bits of that theory.

107:39And there are things that turn out to be very easy

107:43for humans to perform, including young kids, right?

107:46But turn out to be near impossible for machines.

107:50- So what have you learned from the nature of abstraction

107:53from designing that?

107:57Can you clarify what you mean?

107:59One of the things you wanted to try to understand

108:02was this idea of abstraction.

108:06- Yes, so clarifying my own ideas about abstraction

108:10by forcing myself to produce tasks that would require

108:14the ability to produce that form of abstraction

108:18in order to solve them.

108:19- Got it.

108:20Okay, so, and by the way, just to, I mean,

108:23people should check out, I'll probably overlay

108:24if you're watching the video part,

108:26but the grid input output

108:29with the different colors on the grid, that's it.

108:34That's, I mean, it's a very simple world,

108:36but it's kind of beautiful.

108:37- It's very similar to classic IQ test.

108:39Like it's not very original in that sense.

108:41The main difference with IQ tests is that

108:44we make the priors explicit,

108:46which is not usually the case in IQ test.

108:48So you make it explicit that everything should only be built

108:51on top of core knowledge priors.

108:53I also think it's generally more diverse

108:57than IQ test in general.

108:59And it's, it perhaps requires a bit more manual work

109:03to produce solutions because you have to click around

109:06on a grid for a while.

109:08Sometimes the grids can be as large as 30 by 30 cells.

109:12- So how did you come up,

109:13if you can reveal with the questions,

109:18like what's the process of the questions?

109:19Was it mostly you?

109:20- Yes.

109:21- That came up with the questions?

109:22What, how difficult is it to come up with a question?

109:25Like, is this scalable to a much larger number?

109:30If we think, you know, with IQ tests,

109:32you might not necessarily want it to,

109:34or need it to be scalable.

109:36With machines, it's possible you could argue

109:40that it needs to be scalable.

109:41- So there are a thousand questions,

109:44a thousand tasks in total.

109:45Yes.

109:46- Wow.

109:47- Including the tests and the prior test set.

109:49I think it's fairly difficult in the sense that

109:51a big requirement is that every task should be novel

109:56and unique and unpredictable, right?

110:00Like you don't want to create your own little world

110:04that is simple enough that it would be possible

110:08for a human to reverse and generate

110:11and write down an algorithm that could generate

110:14every possible arc task and their solutions,

110:17for instance, that would completely invalidate the test.

110:19So-

110:20- So you're constantly coming up with new stuff.

110:21- You need, yeah, you need a source of novelty,

110:24of unthinkable novelty.

110:27And one thing I found is that as a human,

110:32you are not a very good source of unthinkable novelty.

110:36And so you have to pace the creation of these tasks

110:40quite a bit.

110:41There are only so many unique tasks

110:43that you can do in a given day.

110:44- So I mean, it's coming up with truly original new ideas.

110:48Did psychedelics help you at all?

110:52No, I'm just kidding.

110:53But I mean, that's fascinating to think about.

110:55So you would be like walking or something like that.

110:58Are you constantly thinking of something totally new?

111:02- Yes.

111:03(laughing)

111:05- I mean, this is hard.

111:07This is hard.

111:07- Yeah, I mean, I'm not saying you've done anywhere

111:10near a perfect job at it.

111:12There is some amount of redundancy

111:14and there are many imperfections in arc.

111:16So that said, you should consider arc as a work in progress.

111:19It is not the definitive state

111:24where the arc tasks today

111:26are not definitive states of the test.

111:29I want to keep refining it in the future.

111:32I also think it should be possible

111:35to open up the creation of tasks to a broad audience

111:38to do crowdsourcing.

111:39That would involve several levels of filtering, obviously.

111:44But I think it's possible to apply crowdsourcing

111:46to develop a much bigger and much more diverse arc data set.

111:51That would also be free of potentially,

111:53some of my own personal biases.

111:56- So is there always need to be a part of arc

111:59that's the test, like it's hidden?

112:02- Yes, absolutely.

112:04It is imperative that the test set

112:08that you're using to actually benchmark algorithms

112:11is not accessible to the people developing these algorithms.

112:15Because otherwise what's going to happen

112:16is that the human engineers

112:18are just going to solve the tasks themselves

112:21and code their solution in program form.

112:24But that again, what you're seeing here

112:27is the process of intelligence

112:29happening in the mind of the human.

112:31And then you're just capturing its crystallized output.

112:35But that's crystallized output

112:37is not the same thing as the process that generated it.

112:40It's not intelligent in itself.

112:41- So what, by the way,

112:42the idea of crowdsourcing it is fascinating.

112:44I think the creation of questions

112:49is really exciting for people.

112:51I think there's a lot of really brilliant people out there

112:54that love to create these kinds of stuff.

112:56- Yeah, one thing that kind of surprised me

112:59that I wasn't expecting is that

113:00lots of people seem to actually enjoy arc as a kind of game.

113:05And I was really seeing it as a test,

113:08as a benchmark of fluid general intelligence.

113:13And lots of people just, including kids,

113:17just start enjoying it as a game.

113:18So I think that's encouraging.

113:20- Yeah, I'm fascinated by it.

113:22There's a world of people who create IQ questions.

113:24I think that's a cool activity

113:30for machines and for humans.

113:32And humans are themselves fascinated

113:35by taking the questions,

113:37like measuring their own intelligence.

113:42I mean, that's just really compelling.

113:44It's really interesting to me too.

113:45It helps.

113:46One of the cool things about arc, you said,

113:48it's kind of inspired by IQ tests or whatever,

113:51follows a similar process.

113:53But because of its nature,

113:54because of the context in which it lives,

113:57it immediately forces you to think about

114:00the nature of intelligence

114:01as opposed to just the test of your own.

114:03Like it forces you to really think.

114:05I don't know if it's within the question,

114:09inherent in the question,

114:10or just the fact that it lives in the test

114:13that's supposed to be a test of machine intelligence.

114:15- Absolutely.

114:16As you solve arc tasks as a human,

114:19you will be forced to basically introspect

114:24how you come up with solutions.

114:27And that forces you to reflect

114:29on the human problem-solving process

114:33and the way your own mind generates

114:37abstract representations of the problems it's exposed to.

114:44I think it's due to the fact that

114:47the set of core knowledge priors

114:50that arc is built upon is so small.

114:52It's all a recombination of a very, very small set

114:57of assumptions.

115:00- Okay, so what's the future of arc?

115:02So you held arc as a challenge

115:05as part of like a Kaggle competition.

115:06- Yes.

115:07- Kaggle competition.

115:08And what do you think?

115:12Do you think this is something that continues

115:13for five years, 10 years, like just continues growing?

115:17- Yes, absolutely.

115:18So arc itself will keep evolving.

§13Transcript · 1:55:21–2:04:25

115:21So I've talked about crowdsourcing.

115:22I think that's a good avenue.

115:25Another thing I'm starting is I'll be collaborating

115:30with folks from the psychology department at NYU

115:34to do human testing on arc.

115:36And I think there are lots of interesting questions

115:39you can start asking,

115:39especially as you start correlating machine solutions

115:44to arc tasks and the human characteristics of solutions.

115:50Like for instance, you can try to see

115:52if there's a relationship

115:53between the human perceived difficulty of a task and--

115:58- Machine perceived.

115:59- Yes, and exactly some measure

116:01of machine perceived difficulty.

116:02- Yeah, it's a nice playground

116:04in which to explore this very difference.

116:06It's the same thing as we talked about

116:07with autonomous vehicles.

116:09The things that could be difficult for humans

116:10might be very different than the things that--

116:12- Yes, absolutely.

116:13- And formalizing or making explicit

116:16that difference in difficulty may teach us something

116:20fundamental about intelligence.

116:22- So one thing I think we did well with arc

116:25is that it's proving to be a very actionable test

116:31in the sense that machine performance

116:35and arc started at very much zero initially.

116:39While humans found actually the tasks very easy.

116:43And that alone was like a big red flashing light

116:47saying that something is going on

116:49and that we are missing something.

116:52And at the same time,

116:54machine performance did not stay at zero for very long.

116:57Actually within two weeks of the Kaggle competition,

117:00we started having a non-zero number.

117:03And now the state of the art is around

117:0520% of the test set solved.

117:08And so arc is actually a challenge

117:12where our capabilities start at zero,

117:15which indicates the need for progress.

117:18But it's also not an impossible challenge.

117:20It's not accessible.

117:21You can start making progress basically right away.

117:25At the same time,

117:27we are still very far from having solved it.

117:29And that's actually a very positive outcome

117:32of the competition

117:33is that the competition has proven

117:35that there was no obvious shortcut to solve these tasks.

117:40- Yeah, so the test held up.

117:43- Yeah, exactly.

117:44And that was the primary reason to Kaggle competition

117:46is to check if some clever person

117:51was going to hack the benchmark.

117:54And that did not happen.

117:56Like people were solving the task,

117:57are essentially doing it.

118:01Well, in a way,

118:02they're actually exploring some flaws of arc

118:05that we will need to address in the future,

118:07especially they're essentially anticipating

118:09what sort of tasks may be contained in the test set.

118:13- Right, which is kind of,

118:16yeah, that's the kind of hacking.

118:18It's human hacking of the test.

118:20- Yes, that said,

118:21with the state of the art,

118:23it's like 20% were still very, very far from even level,

118:28which is closer to 100%.

118:31And I do believe that it will take a while

118:35until we reach human parity on arc.

118:40And that by the time we have human parity,

118:43we will have AI systems

118:45that are probably pretty close to human level

118:48in terms of general fluid intelligence,

118:51which is, I mean,

118:52they're not gonna be necessarily human-like.

118:54They're not necessarily,

118:56you would not necessarily recognize them

118:59as being an AGI,

119:01but they would be capable of a degree of generalization

119:05that matches the generalization

119:09performed by human fluid intelligence.

119:11- Sure.

119:12I mean, this is a good point

119:13in terms of general fluid intelligence to mention.

119:17In your paper,

119:17you described different kinds of generalizations,

119:20local, broad, extreme,

119:23and there's a kind of a hierarchy that you form.

119:25So when we say generalizations,

119:29what are we talking about?

119:31What kinds are there?

119:33- Right.

119:34So generalization is a very old idea.

119:37I mean, it's even older than machine learning.

119:39In the context of machine learning,

119:40you say a system generalizes

119:43if it can make sense of an input it has not yet seen.

119:48And that's what I would call a system-centric generalization.

119:54It's generalization with respect to novelty

119:59for the specific system you're considering.

120:02So I think a good test of intelligence

120:05should actually deal with developer-aware generalization,

120:09which is slightly stronger than system-centric generalization.

120:13So developer-aware generalization would be

120:16the ability to generalize to novelty or uncertainty

120:21that not only the system itself has not access to,

120:24but the developer of the system

120:26could not have access to either.

120:29- That's a fascinating meta-definition.

120:32So like the system,

120:33it's basically the edge case thing

120:37we're talking about with autonomous vehicles.

120:39Neither the developer nor the system

120:41know about the edge cases they encounter.

120:44So it's up to,

120:46the system should be able to generalize the thing

120:47that nobody expected,

120:51neither the designer of the training data

120:53nor obviously the contents of the training data.

120:59That's a fascinating definition.

121:00- So you can see generalization,

121:01degrees of generalization as a spectrum.

121:04And the lowest level is what machine learning

121:08is trying to do,

121:09is the assumption that any new situation

121:13is gonna be sampled from a static distribution

121:17of possible situations.

121:18And that you already have a representative sample

121:21of the distribution, that's your training data.

121:23And so in machine learning,

121:24you generalize to a new sample from a known distribution.

121:28And the ways in which your new sample

121:31will be new or different

121:33are ways that are already understood

121:36by the developers of the system.

121:39So you are generalizing to known unknowns

121:43for one specific task.

121:45That's what you would call robustness.

121:47You are robust to things like noise,

121:49small variations and so on.

121:50For one fixed known distribution

121:56that you know through your training data.

121:59And a higher degree would be flexibility

122:04in machine intelligence.

122:06So flexibility would be something like

122:08an L5 self-driving car,

122:11or maybe a robot that can,

122:14pass the coffee cup test,

122:16which is the notion that you'd be given

122:19a random kitchen somewhere in the country

122:22and you would have to,

122:23go make a cup of coffee in that kitchen.

122:26So flexibility would be the ability

122:30to deal with unknown unknowns.

122:33So things that could not,

122:35dimension survivability

122:36that could not have been possibly foreseen

122:39by the creators of the system

122:41within one specific task.

122:42So generalizing to the long tail of situations

122:46in self-driving for instance,

122:47would be flexibility.

122:48So you have robustness, flexibility,

122:51and finally you would have extreme generalization,

122:53which is basically flexibility,

122:56but instead of just considering one specific domain

123:01like driving or domestic robotics,

123:03you're considering an open-ended range

123:06of possible domains.

123:07So a robot would be capable of extreme generalization

123:12if let's say it's designed and trained

123:15for cooking for instance.

123:18And if I buy the robots

123:22and if I'm able,

123:24if it's able to teach itself gardening

123:27in a couple of weeks,

123:28it would be capable of extreme generalization for instance.

123:32- So the ultimate goal is extreme generalization.

123:34- Yes.

123:35So creating a system that is so general

123:39that it could essentially achieve a human skill parity

123:43of arbitrary task and arbitrary domains

123:47with the same level of improvisation

123:50and adaptation power as humans

123:52when it encounters new situations.

123:55And it would do so over basically the same range

123:59of possible domains and tasks as humans

124:02and using essentially the same amount

124:05of training experience of practice as humans would require.

124:07That would be human level extreme generalization.

124:10So I don't actually think humans are anywhere near

124:15the optimal intelligence bound if there is such a thing.

124:20So I think-

124:22- For humans or in general?

124:23- In general.

124:25I think it's quite likely that there is

§14Transcript · 2:04:27–2:14:00

124:27an hard limit to how intelligent any system can be.

124:32But at the same time,

124:34I don't think humans are anywhere near that limit.

124:38- Yeah, last time I think we talked,

124:40I think you had this idea that we're only as intelligent

124:44as the problems we face.

124:46Sort of-

124:47- Yes, intelligence-

124:49- We are upper bounded by the problem.

124:51- In a way, yes.

124:51We are bounded by our environments

124:55and we are bounded by the problems we try to solve.

124:58- Yeah, yeah.

124:59What do you make of Neuralink

125:01and outsourcing some of the brain power,

125:05like brain computer interfaces?

125:07Do you think we can expand our,

125:10augment our intelligence?

125:13- I am fairly skeptical of neural interfaces

125:18because they are trying to fix one specific bottleneck

125:23in human machine cognition,

125:26which is the bandwidths bottleneck,

125:28input and output of information in the brain.

125:31And my perception of the problem is that

125:36bandwidth is not at this time a bottleneck at all,

125:40meaning that we already have senses that enable us

125:44to take in far more information

125:47than what we can actually process.

125:50- Well, to push back on that a little bit,

125:53to sort of play devil's advocate a little bit,

125:55is if you look at the internet, Wikipedia,

125:57let's say Wikipedia,

125:59I would say that humans,

126:00after the advent of Wikipedia,

126:03are much more intelligent.

126:05- Yes, I think that's a good one,

126:07but that's also not about,

126:09that's about externalizing our intelligence

126:14via information processing systems,

126:18external processing systems,

126:19which is very different from brain computer interfaces.

126:23- Right, but the question is whether

126:26if we have direct access,

126:28if our brain has direct access to Wikipedia without-

126:31- Your brain already has direct access to Wikipedia.

126:34It's on your phone,

126:35and you have your hands and your eyes

126:38and your ears and so on to access that information.

126:42And the speed at which you can access it-

126:44- Is bottlenecked by the cognition.

126:45- I think it's already close,

126:48fairly close to optimal,

126:49which is why speed reading, for instance, does not work.

126:53The faster you read, the less you understand.

126:56- But maybe it's 'cause it uses the eyes.

126:58So maybe-

126:59- So I don't believe so.

127:01I think the brain is very slow.

127:04It typically operates,

127:06the fastest things that happen in the brain

127:08are at the level of 50 milliseconds.

127:10Forming a conscious thought

127:13can potentially take entire seconds, right?

127:16And you can already read pretty fast.

127:19So I think the speed at which you can take information in,

127:23and even the speed at which you can output information

127:26can only be very incrementally improved.

127:29- Maybe there's a-

127:30- I think that if you're a very, very fast typer,

127:32if you're a very trained typer,

127:34the speed at which you can express your thoughts

127:36is already the speed at which you can form your thoughts.

127:40- Right, so that's kind of an idea

127:42that there are fundamental bottlenecks to the human mind.

127:47But it's possible that everything we have in the human mind

127:51is just to be able to survive in the environment.

127:54And there's a lot more to expand.

127:58Maybe, you said the speed of the thought.

128:02So I think augmenting human intelligence

128:06is a very valid and very powerful avenue, right?

128:09And that's what computers are about.

128:12In fact, that's what all of culture

128:15and civilization is about.

128:16They are, culture is externalised cognition,

128:20and we rely on culture to think constantly.

128:23- Yeah, I mean, that's another way, yeah.

128:26- Not just computers, not just phones and the internet.

128:29All of culture, like language, for instance,

128:32is a form of externalised cognition.

128:34Books are obviously externalised cognition.

128:37- Yeah, that's a great point.

128:38- And you can scale that externalised cognition

128:42far beyond the capability of the human brain.

128:45And you could see, civilization itself,

128:48it has capabilities that are far beyond

128:52any individual brain.

128:54And we'll keep scaling it,

128:55because it's not rebound by individual brains.

128:59It's a different kind of system.

129:01- Yeah, and that system includes non-humans.

129:05First of all, it includes all the other biological systems,

129:08which are probably contributing

129:10to the overall intelligence of the organism.

129:12And then computers are part of it.

129:14- Non-human systems are probably not contributing much,

129:16but AIs are definitely contributing to that.

129:19Like Google Search, for instance, is a big part of it.

129:22- Yeah, yeah.

129:27A huge part.

129:28A part that we can't probably introspect.

129:31Like how the world has changed in the past 20 years,

129:33it's probably very difficult for us

129:35to be able to understand until...

129:38Of course, whoever created the simulation we're in

129:40is probably doing metrics, measuring the progress.

129:44There was probably a big spike in performance.

129:47They're enjoying this.

129:50So what are your thoughts on the Turing Test

129:56and the Lobner Prize, which is the...

129:58One of the most famous attempts

130:02at the test of human intelligence,

130:04sorry, of artificial intelligence,

130:07by doing a natural language open dialogue test

130:11that's judged by humans as far as how well the machine did.

130:16- So I'm not a fan of the Turing Test itself

130:22or any of its variants for two reasons.

130:25So first of all,

130:26it's really coping out of trying to define

130:35and measure intelligence

130:37because it's entirely outsourcing that

130:40to a panel of human judges.

130:43And these human judges,

130:44they may not themselves have any proper methodology.

130:49They may not themselves have any proper definition

130:52of intelligence.

130:53They may not be reliable.

130:54So the Turing Test is already failing

130:57one of the core psychometrics principles,

130:59which is reliability, because you have biased human judges.

131:04It's also violating the standardization requirement

131:08and the freedom from bias requirement.

131:10And so it's really a cope out

131:12because you are outsourcing everything that matters,

131:15which is precisely describing intelligence

131:18and finding a standard on test to measure it.

131:22You're outsourcing everything to people.

131:25So it's really a cope out.

131:26And by the way, we should keep in mind

131:28that when Turing proposed the imitation game,

131:33it was not meaning for the imitation game

131:36to be an actual goal for the field of AI,

131:40an actual test of intelligence.

131:42It was using the imitation game as a thought experiment

131:48in a philosophical discussion in his 1950 paper.

131:53He was trying to argue that theoretically

131:58it should be possible for something very much

132:03like the human mind, indistinguishable from the human mind

132:06to be encoded in a Turing machine.

132:08And at the time that was a very daring idea.

132:13It was stretching credulity.

132:16But nowadays I think it's fairly well accepted

132:20that the mind is an information processing system

132:22and that you could probably encode it into a computer.

132:25So another reason why I'm not a fan of this type of test

132:29is that the incentives that it creates

132:34are incentives that are not conducive

132:37to proper scientific research.

132:40If your goal is to trick,

132:43to convince a panel of human judges

132:46that they're talking to a human,

132:48then you have an incentive to rely on tricks

132:53and prestidigitation.

132:55In the same way that let's say you're doing physics

132:59and you want to solve teleportation.

133:01And what if the test that you set out to pass

133:04is you need to convince a panel of judges

133:07that teleportation took place

133:09and they're just sitting there

133:10and watching what you're doing.

133:12And that is something that you can achieve with,

133:16you know, David Copperfield could achieve it

133:19in his show at Vegas, right?

133:21But what he's doing is very elaborate,

133:25but it's not actually, it's not physics.

133:29It's not making any progress

133:30in our understanding of the universe, right?

133:32- To push back on that, it's possible,

133:34that's the hope with these kinds of subjective evaluations,

133:39is that it's easier to solve it generally

133:42than it is to come up with tricks

133:44that convince a large number of judges.

133:46That's the hope.

133:47- In practice, what it turns out

133:48that it's very easy to deceive people

133:50in the same way that, you know,

133:51you can do magic in Vegas.

133:54You can actually very easily convince people

133:57that they're talking to a human

133:58when they're actually talking to an algorithm.

134:00- I just disagree.

§15Transcript · 2:14:01–2:22:46

134:01I disagree with that.

134:02I think it's easy.

134:03I would push, it's not easy.

134:06It's doable.

134:08- It's very easy because-

134:09- I wouldn't say it's very easy though.

134:10- We are biased.

134:12Like we have theory of mind.

134:13We are constantly projecting emotions, intentions,

134:18agent-ness.

134:21Agent-ness is one of our core innate priors, right?

134:24We are projecting these things on everything around us.

134:26Like if you paint a smiley on a rock,

134:31the rock becomes happy in our eyes.

134:33And because we have this extreme bias

134:36that permits everything we see around us,

134:39it's actually pretty easy to trick people.

134:41Like it is a trick people.

134:44- I so totally disagree with that.

134:45You brilliantly put, there's a huge,

134:47the anthropomorphization that we naturally do,

134:51the agent-ness of that word.

134:53Is that a real word?

134:54- No, it's not a real word.

134:55- I like it.

134:56- But it's a good word.

134:57It's a useful word.

134:58- It's a useful word.

134:58Let's make it real.

134:59It's a huge help.

135:01But I still think it's really difficult to convince.

135:03If you do like the Alexa prize formulation,

135:07where you talk for an hour,

135:10like there's formulations of the test you can create

135:12where it's very difficult.

135:13- So I like the Alexa prize better

135:16because it's more pragmatic.

135:18It's more practical.

135:19It's actually incentivizing developers

135:22to create something that's useful

135:24as a human machine interface.

135:29So that's slightly better than just the imitation.

135:31- So I like it.

135:32Your idea is like a test,

135:35which hopefully will help us

135:37in creating intelligent systems as a result.

135:39Like if you create a system that passes it,

135:41it'll be useful for creating further intelligent systems.

135:44- Yes, at least.

135:46- Yeah.

135:46I mean, just to kind of comment,

135:49I'm a little bit surprised

135:51how little inspiration people draw

135:54from the Turing test today.

135:56The media and the popular press

135:58might write about it every once in a while.

136:00The philosophers might talk about it.

136:03But like most engineers are not really inspired by it.

136:07And I know you don't like the Turing test,

136:11but we'll have this argument another time.

136:13There's something inspiring about it, I think.

136:17- As a philosophical device in a philosophical discussion,

136:21I think there is something very interesting about it.

136:23I don't think it is in practical terms.

136:26I don't think it's conducive to progress.

136:29And one of the reasons why is that,

136:32I think being very human-like,

136:34being indistinguishable from a human

136:36is actually the very last step

136:39in the creation of machine intelligence.

136:40That the first AI that will show strong generalization

136:45that will actually implement

136:50human-like broad cognitive abilities,

136:53they will not actually behave or look anything like humans.

136:57Human likeness is the very last step in that process.

137:01And so a good test is a test that points you

137:04towards the first step on the ladder,

137:07not towards the top of the ladder.

137:08- So to push back on that,

137:10so I guess I usually agree with you on most things.

137:13I remember you, I think at some point tweeting

137:15something about the Turing test

137:17not being counterproductive or something like that.

137:20And I think a lot of very smart people agree with that.

137:23Computation speaking, not a very smart person.

137:31I disagree with that 'cause I think there's some magic

137:33to the interactivity with other humans.

137:36So to play devil's advocate on your statement,

137:39it's possible that in order to demonstrate

137:42the generalization abilities of a system,

137:45you have to in conversation show your ability

137:50to adjust, adapt to the conversation,

137:55through not just like as a standalone system,

137:58but through the process of like the interaction,

138:01the game theoretic, where you really are changing

138:06the environment by your actions.

138:09So in the ARC challenge, for example, you're an observer.

138:12You can't scare the test into changing.

138:17You can't talk to the test.

138:19You can't play with it.

138:21So there's some aspect of that interactivity

138:24that becomes highly subjective,

138:25but it feels like it could be conducive

138:28to generalizability. - Yeah, I think you make

138:30a great point.

138:31The interactivity is a very good setting

138:33to force a system to show adaptation,

138:36to show generalization.

138:37That said, you're at the same time,

138:42it's not something very scalable

138:43because you rely on human judges.

138:46It's not something reliable

138:47because the human judges may not.

138:49- So you don't like human judges.

138:50- Basically, yes.

138:51And I think, so I love the idea of interactivity.

138:55I initially wanted an ARC test

138:59that had some amount of interactivity

139:01where your score on a task would not be one or zero,

139:04if you can solve it or not,

139:05but would be the number of attempts

139:10that you can make before you hit the right solution,

139:14which means that now you can start applying

139:16the scientific method as you solve ARC tasks,

139:19that you can start formulating hypotheses

139:22and probing the system to see whether the hypothesis,

139:26the observation will match the hypothesis or not.

139:28- It would be amazing if you could also,

139:30even higher level than that,

139:32measure the quality of your attempts,

139:35which of course is impossible,

139:36but again, that gets subjective.

139:38How good was your thinking?

139:40- Yeah, how efficient was,

139:43so one thing that's interesting about this notion

139:46of scoring you as how many attempts you need

139:49is that you can start producing tasks

139:51that are way more ambiguous, right?

139:54- Right.

139:56- Because-- - Exactly, so you can--

139:57- With the different attempts,

139:59you can actually probe that ambiguity, right?

140:03- Right, so that's in a sense,

140:05which is how good can you adapt to the uncertainty

140:10and reduce the uncertainty?

140:15- Yes, it's how fast is the efficiency

140:19with which you reduce uncertainty in problem space, exactly.

140:23- Very difficult to come up with that kind of test though.

140:24- Yeah, so I would love to be able

140:27to create something like this.

140:28In practice, it would be very, very difficult, but yes.

140:31- But I mean, what you're doing,

140:34what you've done with the ARC challenge is brilliant.

140:37I'm also not, I'm surprised that it's not more popular,

140:40but I think it's picking up--

140:41- It does its niche, it does its niche, yeah.

140:44- Yeah, what are your thoughts about another test

140:46that I talked with Marcus Hutter?

140:48He has the Hutter Prize for compression of human knowledge,

140:51and the idea is really sort of quantify,

140:55like reduce the test of intelligence purely

140:57to just the ability to compress.

140:59What's your thoughts about this intelligence as compression?

141:04- I mean, it's a very fun test

141:07because it's such a simple idea.

141:09Like you're given Wikipedia, basic English Wikipedia,

141:13and you must compress it.

141:15And so it stems from the idea that cognition is compression,

141:21that the brain is basically a compression algorithm.

141:24This is a very old idea.

141:25It's a very, I think, striking and beautiful idea.

141:30I used to believe it.

141:31I eventually had to realize that it was

141:35very much a flawed idea.

141:36So I no longer believe that cognition is compression.

141:41But I can tell you what's the difference.

141:44So it's very easy to believe that cognition and compression

141:48are the same thing because,

141:50so Jeff Hawkins, for instance,

141:52says that cognition is prediction.

141:54And of course, prediction is basically

141:57the same thing as compression, right?

141:58It's just including the temporal axis.

142:02And it's very easy to believe this

142:05because compression is something that we do all the time,

142:07very naturally.

142:09We are constantly compressing information.

142:12We are constantly trying,

142:15we have this bias towards simplicity.

142:17We're constantly trying to organize things in our mind

142:21and around us to be more regular, right?

142:24So it's a beautiful idea.

142:26It's very easy to believe.

142:28There is a big difference between what we do

142:31with our brains and compression.

142:34So compression is actually kind of a tool

142:38in the human cognitive toolkits

142:40that is used in many ways, but it's just a tool.

142:43It is not, it is a tool for cognition.

142:46It is not cognition itself.

§16Transcript · 2:22:47–2:32:44

142:47And the big fundamental difference

142:50is that cognition is about being able

142:54to operate in future situations

142:57that include fundamental uncertainty and novelty.

143:02So for instance, consider a child at age 10.

143:06And so they have 10 years of life experience.

143:10They've gotten pain, pleasure, rewards,

143:12and punishment in a period of time.

143:16If you were to generate the shortest behavioral program

143:21that would have basically run that child

143:25over those 10 years in an optimal way, right?

143:29The shortest optimal behavioral program

143:32given the experience of that child so far.

143:34Well, that program, that compressed program,

143:37this is what you would get if the mind of the child

143:40was a compression algorithm essentially,

143:42would be utterly unable, inappropriate

143:47to process the next 70 years in the life of that child.

143:53So in the models we build of the world,

143:59we are not trying to make them actually optimally compressed.

144:03We are using compression as a tool

144:06to promote simplicity and efficiency in our models,

144:10but they are not perfectly compressed

144:12because they need to include things

144:15that are seemingly useless today,

144:17that have seemingly been useless so far,

144:20but that may turn out to be useful in the future

144:24because you just don't know the future.

144:25And that's the fundamental principle

144:28that cognition, that intelligence arises from,

144:31is that you need to be able to run

144:33appropriate behavioral programs,

144:35except you have absolutely no idea

144:37what sort of context, environment, and situation

144:40they're going to be running in.

144:42And you have to deal with that uncertainty,

144:44with that future normality.

144:46So an analogy that you can make is with investing,

144:51for instance, if I look at the past, you know,

144:5720 years of stock market data

144:59and I use a compression algorithm

145:01to figure out the best trading strategy,

145:04it's going to be, you know, you buy Apple stock,

145:06then maybe the past few years

145:07you buy Tesla stock or something.

145:10But is that strategy still going to be true

145:13for the next 20 years?

145:14Well, actually, probably not,

145:17which is why if you're a smart investor,

145:21you're not just going to be following the strategy

145:25that corresponds to compression of the past.

145:28You're going to be following,

145:30you're going to have a balanced portfolio, right?

145:34Because you just don't know what's going to happen.

145:38- I mean, I guess in that same sense,

145:40the compression is analogous to what you talked about,

145:43which is like local or robust generalization

145:45versus extreme generalization.

145:47It's much closer to that side of being able to generalize

145:52in the local sense.

145:53- That's why, you know, as humans,

145:54as when we are children, in our education,

145:59so a lot of it is driven by play, driven by curiosity.

146:03We are not efficiently compressing things.

146:07We're actually exploring.

146:09We are retaining all kinds of things

146:14from our environment that seem to be completely useless

146:19because they might turn out to be eventually useful, right?

146:24And that's what cognition is really about.

146:26And what makes it antagonistic to compression

146:29is that it is about hedging for future uncertainty.

146:34And that's antagonistic to compression.

146:35- Yes, efficiently hedging.

146:37- So cognition leverages compression

146:40as a tool to promote efficiency, right?

146:44And so in that sense, in our models.

146:47- It's like Einstein said, make it simpler,

146:50but not, however that quote goes, but not too simple.

146:54So you want to, compression simplifies things,

146:57but you don't want to make it too simple.

147:00- Yes, so a good model of the world

147:02is going to include all kinds of things

147:04that are completely useless, actually,

147:06just because, just in case.

147:08Because you need diversity

147:09in the same way that's in your portfolio.

147:11You need all kinds of stocks

147:12that may not have performed well so far,

147:14but you need diversity.

147:15And the reason you need diversity

147:16is because fundamentally you don't know what you're doing.

147:19And the same is true of the human mind

147:22is that it needs to behave appropriately in the future.

147:26And it has no idea what the future is going to be like.

147:29It's a bit, it's not going to be like the past.

147:31So compressing the past is not appropriate

147:33because the past is not,

147:35is not proactive with the future.

147:39- Yeah, history repeats itself, but not perfectly.

147:43I don't think I asked you last time

147:47the most inappropriately absurd question.

147:50We've talked a lot about intelligence,

147:54but the bigger question from intelligence is of meaning.

147:59Intelligence systems are kind of goal-oriented.

148:02There's, they're always optimizing for goal.

148:05If you look at the Hutter Prize, actually,

148:07I mean, there's always a clean formulation of a goal,

148:10but the natural questions for us humans,

148:14since we don't know our objective function

148:16is what is the meaning of it all?

148:18So the absurd question is what,

148:21Francois Chollet, do you think is the meaning of life?

148:25- What's the meaning of life?

148:26Yeah, that's a big question.

148:31And I think I can give you my answer,

148:35or at least one of my answers.

148:38And so, you know, the one thing that's very important

148:43in understanding who we are is that

148:46everything that makes up,

148:49that makes up ourselves, that makes up who we are,

148:53even your most personal thoughts

148:56is not actually your own, right?

148:59Like even your most personal thoughts

149:01are expressed in words that you did not invent

149:04and are built on concepts and images

149:08that you did not invent.

149:10We are very much cultural beings, right?

149:14We are made of culture.

149:16What makes us different from animals, for instance, right?

149:20So we are, everything about ourselves is an echo

149:25of the past, an echo of people who lived before us, right?

149:29That's who we are.

149:31And in the same way, if we manage to contribute something

149:36to the collective edifice of culture,

149:40a new idea, maybe a beautiful piece of music,

149:44a work of art, a grand theory,

149:47a new words maybe,

149:51that something is going to become a part

149:55of the minds of future humans, essentially forever.

150:00So everything we do creates ripples, right?

150:04That propagates into the future.

150:06And that's, in a way, this is our path to immortality

150:11is that as we contribute things to culture,

150:17culture in turn becomes future humans.

150:21And we keep influencing people,

150:24thousands of years from now.

150:27So our actions today create ripples.

150:30And these ripples, I think,

150:33basically sum up the meaning of life.

150:37Like in the same way that we are the sum

150:40of the interactions between many different ripples

150:45that came from our past,

150:47we are ourselves creating ripples

150:48that will propagate into the future.

150:50And that's why we should be,

150:53this seems like perhaps a naive thing to say,

150:56but we should be kind to others during our time on earth

151:01because every act of kindness creates ripples.

151:05And in reverse, every act of violence also creates ripples.

151:09And you want to carefully choose

151:12which kind of ripples you want to create

151:14and you want to propagate into the future.

151:16- And in your case, first of all, beautifully put,

151:19but in your case, creating ripples into the future human

151:23and future AGI systems.

151:27- Yes. - It's fascinating.

151:29- All success.

151:30- I don't think there's a better way to end it, Francois.

151:35As always, for a second time,

151:37and I'm sure many times in the future,

151:39it's been a huge honor.

151:40You're one of the most brilliant people

151:43in the machine learning, computer science,

151:46science world.

151:47Again, it's a huge honor.

151:48Thanks for talking today.

151:49- It's been a pleasure.

151:50Thanks a lot for having me.

151:52Really appreciate it.

151:54- Thanks for listening to this conversation

151:55with Francois Chollet.

151:56And thank you to our sponsors,

151:58Babbel, Masterclass, and Cash App.

152:01Click the sponsor links in the description

152:03to get a discount and to support this podcast.

152:06If you enjoy this thing, subscribe on YouTube,

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152:11follow on Spotify, support on Patreon,

152:14or connect with me on Twitter @LexFriedman.

152:16And now let me leave you with some words

152:19from Rene Descartes in 1668,

152:22an excerpt of which Francois includes

152:24in his "On the Measure of Intelligence" paper.

152:27"If there were machines which bore a resemblance

152:30"to our bodies and imitated our actions

152:32"as closely as possible for all practical purposes,

152:36"we should still have two very certain means

152:38"of recognizing that they were not real men.

152:42"The first is that they could never use words

152:44"or put together signs as we do

§17Transcript · 2:32:46–2:34:14

152:46"in order to declare our thoughts to others.

152:49"For we can certainly conceive of a machine so constructed

152:53"that it utters words and even utters words

152:55"that correspond to bodily actions

152:57"causing a change in its organs.

152:59"But it is not conceivable that such a machine

153:02"should produce different arrangements of words

153:05"so as to give an appropriately meaningful answer

153:08"to whatever is said in its presence

153:10"as the dullest of men can do."

153:12Here Descartes is anticipating the Turing test

153:15and the argument still continues to this day.

153:17"Secondly," he continues,

153:20"even though some machines might do some things

153:23"as well as we do them, or perhaps even better,

153:26"they would inevitably fail in others,

153:28"which would reveal that they're acting

153:30"not from understanding,

153:32"but only from the disposition of their organs."

153:35This is an incredible quote.

153:38For whereas reason is a universal instrument

153:43which can be used in all kinds of situations,

153:46these organs need some particular action.

153:49Hence, it is for all practical purposes impossible

153:52for a machine to have enough different organs

153:54to make it act in all the contingencies of life

153:57in the way in which our reason makes us act.

154:01That's the debate between mimicry memorization

154:05versus understanding.

154:07So thank you for listening and hope to see you next time.

154:11(upbeat music)

154:14(upbeat music)

— A LITTLE MORE TO THINK ABOUT. —