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Intelligence Is Legos [Dr. Jeff Beck]

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Intelligence Is Legos [Dr. Jeff Beck]

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1411 segments

0:00

Geometric deep learning is a big part of

0:01

like is a big part of the stack if for

0:04

no other reason than when we talk about

0:05

like modeling the physical world that

0:07

means like incorporating the symmetries

0:09

that exist in the physical world. It's

0:11

like we're highly motivated to employ a

0:14

lot of those methods and techniques.

0:16

>> But is the world written in code or do

0:18

you mean exploiting the regularities in

0:20

the code that seem to have some

0:22

>> exploiting the regularities? No, it's

0:24

like look we it things are it is the

0:25

world is translation invariant. The

0:27

world is like rotation. Well, not really

0:29

because there's gravity, but like in

0:31

principle, you know, there is a

0:33

principal axis, but it's certainly

0:35

rotationally invariant in the xy plane.

0:37

>> Yeah.

0:38

>> Um, and if you if you want to have a

0:40

good model of the world as it actually

0:42

is, it should incorporate those

0:44

features. Of course, you can discover

0:46

it, you know, in a brute forcy way, but

0:49

the mathematician in me really wants to

0:50

build build the symmetries in. And

0:53

fortunately, we've got a lot of great

0:54

tools that were developed over the last

0:55

several years that can do that. What's

0:57

your view on agency?

0:58

>> If I'm being, you know, like an FEP

1:01

purist, I have to sort of say like, oh,

1:03

well, there's no difference between, you

1:04

know, an agent and an object in in a

1:07

very real way, or at least there's

1:08

nothing structurally distinct between

1:10

what how we model an agent and how we

1:12

model an object. Um, it's really just a

1:14

question of of degrees, right? An agent

1:17

is is a really sophisticated object,

1:20

right? It has internal states that

1:22

represent things over very long time

1:24

scales. um you know uh it has uh

1:28

sophisticated policies that are context

1:30

dependent which is basically saying

1:32

really long time scales again um and

1:34

things like that.

1:35

>> Yeah. You know um there's the kind of

1:38

the philosophical highbrow notion of

1:40

agency that we introduce notions of um

1:44

intentionality and self-causation and

1:47

things like that. I mean the the really

1:49

nononsense version of an agency is it

1:51

it's just it's just a thing which acts

1:54

and performs some kind of computation

1:57

and I guess you could almost model

1:59

anything as an agent you know.

2:01

>> Yeah. Well so if if if your definition

2:03

of an agent is something that executes a

2:05

policy then anything is an agent right a

2:07

rock is an agent right every everything

2:09

has you know it's an input a policy is

2:12

an input output relationship. When many

2:14

people talk about agents, they they're

2:17

adding a few they're adding um a few

2:19

additional elements that I think have a

2:22

lot to do with how the policy is

2:24

computed, right? So, for example, when

2:28

we think of how the difference between

2:29

like us and like like really like

2:32

amiebas, we we often cite things like

2:35

planning, counterfactual reasoning,

2:38

goaloriented behavior, right? We're

2:40

specifying things that that um have that

2:44

that are specific mean that that are all

2:46

related to how it is we compute our

2:49

policies, right? They're latent

2:51

variables that represent policies um

2:54

that are uh you know that are compatible

2:56

with like well reinforcement learning,

2:58

right? And um and that's the defining

3:01

characteristic of an agent. But you

3:03

could very easily just sort of say like

3:05

from an outside perspective if you can't

3:07

look at how someone or something is

3:08

doing the computations if the only thing

3:10

you observe is the policy

3:13

right does that mean that you can never

3:14

conclude that something's an agent and I

3:17

would say no right you'd still like to

3:19

be able to conclude that this is an

3:20

agent even though the only thing I ever

3:23

get to measure is its policy

3:25

>> but do you think we should have some

3:26

notion of the strength of an agent

3:28

>> the strength of an agent or how is this

3:31

like a measure of agency is that what

3:32

you either. Yeah. So, I mean, I think

3:35

you could use like notions of like

3:37

transfer entropy and things like that in

3:40

order to estimate like the timetable

3:42

over which something is incorporating

3:44

information or the degree to which it's

3:46

taken into it. It it exhibits a context

3:48

dependent behavior and things like that

3:50

and that would be a pretty good measure.

3:53

Now, is it normative? No, it's not. It's

3:55

it's a but it is a measure and you could

3:57

use things like that. But at that point,

3:58

you're really just talking again about

3:59

policy sophistication,

4:01

right? Not does it have a reward

4:03

function? Like is it actually executing

4:05

planning?

4:06

>> Yeah. I mean certainly intuitively

4:08

agents to me seem to be kind of causally

4:11

disconnected

4:13

because they're planning into the

4:14

future. They are not impulse response

4:17

machines. They're not just, you know,

4:19

part of the mass of things going on

4:20

around them. They are just obviously

4:23

disconnected from the locality.

4:25

>> So here the trick is is that okay, so

4:27

I've got this agent and I know exactly

4:29

what it does, right? It takes into it

4:31

takes into account information. um it

4:33

rolls out future you know internally it

4:36

rolls out a whole bunch of like future

4:38

uh consequences of of various different

4:40

actions or plans that it could take it

4:42

selects the best one and then it

4:43

executes it right so all of those

4:46

variables all of those variables that

4:47

were that occurred inside right from the

4:50

outside perspective it just looked like

4:52

a function transformation right it it's

4:55

I don't unless I unless I'm somehow

4:57

going in and recording and somehow

4:59

demonstrating the fact that the manner

5:00

in which it is calculating its policy

5:03

you know, like involved doing those

5:05

rollouts,

5:07

right? I wouldn't be able to show that

5:09

it's actually doing those rollouts. I

5:10

would just be able to conclude it has a

5:12

really sophisticated policy. So, can you

5:14

conclude that something isn't is is so

5:16

so the question is how do you identify

5:17

something is actually doing planning?

5:20

And I think that's a really hard

5:21

question as opposed to having an

5:22

incredibly sophisticated policy. I think

5:25

my my intuition is if it feels to me

5:28

that a function a simple input output

5:30

mapping can't be an agent. And and in a

5:32

way this is related to what we were

5:33

talking about with grounding. You know,

5:35

it it seems that when things are

5:36

physically embedded in the world, then

5:39

they're more likely to be agents. This

5:41

functionalist idea that just a bit of

5:44

computer code running on a machine, it

5:46

kind of feels like that can't be an

5:47

agent.

5:48

>> It does. So suppose I coded it up so it

5:51

was doing all of that planning. It's

5:54

like gets its inputs, does some crazy

5:56

like massive Monte Carlo research, picks

5:58

the best policy possible, and then

6:00

executes it. Now, you don't observe any

6:02

of that, right? Because you know what's

6:05

going on. You could say, "Oh, well, it's

6:06

it's clearly like executing, you know,

6:08

this is it's doing planning and

6:09

counterfactual reasoning. It's going on

6:11

like look there it is because you coded

6:13

it, so you know it's doing it." But if

6:15

you're looking at it from the outside,

6:17

right, it, you know, if you don't know

6:19

what's happening inside, it's going, you

6:22

know, all you have access to is, oh,

6:24

here's the action that it that it that

6:26

it did given this long series of inputs.

6:30

And so it's it's really hard to identify

6:33

what you know something as an agent per

6:36

se from the outside. You kind of have to

6:38

know what's going on inside. This by the

6:40

way is why I don't think that like you

6:42

know you know these sort of prediction

6:43

based approaches to like AI

6:46

um are necess you know you could sort of

6:48

say well it's not really doing anything

6:51

even remotely agentic unless it's

6:54

executing it's doing planning and

6:55

counterfactual reason. So like your

6:57

chess program is is like oh clearly it's

6:59

doing some planning and counterfactual

7:01

reasoning because you know it's doing it

7:03

but um but it but you could like write I

7:07

could describe the exact same set of

7:08

behaviors just with a policy function. I

7:10

I think the counterfactual thing is is

7:12

an important feature here because we

7:14

could take something which was conscious

7:15

or something which had agency and we

7:17

could just take a trace of the actual

7:20

path which was found and now we've just

7:22

got this a reductio at absurd but you

7:24

know now we've just got a computational

7:26

trace and that thing clearly has now

7:28

lost whatever agency or consciousness it

7:30

had. So there's something about

7:32

considering all of the possibilities.

7:34

>> Yeah. Yeah. I think so in my mind that

7:36

is the fundamental feature of of of of

7:38

an agent. like if you can show that it's

7:40

engaged in planning counterfactual

7:41

reasoning and and then it's definitely

7:43

an agent. My my argument is just simply

7:46

that that's hard to do unless you crack

7:48

it open and see what's going on inside.

7:50

Now, you could take a a pragmatic view

7:53

and say, well, if the simplest

7:55

computational model of the behavior,

7:58

model it as if it was doing planning and

8:00

counterfactual reasoning, then you can

8:02

draw an implicit conclusion that oh yes,

8:04

well, I may as well say it's an agent.

8:07

And that's kind of the approach that

8:08

I've taken. So like one of the things

8:09

that comes out of the physics discovery

8:11

algorithm is that you apply it to agents

8:12

and what do you get? Well, you get a

8:14

model. Now bear in mind I called them

8:16

all objects before and I didn't change

8:18

anything to make it special to an actual

8:20

agent, right? But what I do have the

8:23

ability to do because of the model is I

8:24

can look at the internal states

8:27

associated with that object that I want

8:28

to call an agent and look at how

8:30

sophisticated it is.

8:32

>> Right? And that degree of sophistication

8:35

is what allows me to say, "Oh, well, I'm

8:37

going to go ahead and say that like and

8:38

I like the whole idea. It's a great

8:39

idea. Like it's have a metric, right?

8:42

And I'm sure it would be something that

8:43

would effectively be like transfer

8:44

entropy or something like that." But we

8:45

have this metric on like, well, how

8:47

sophisticated were the internal states

8:49

that were necessary in order to generate

8:50

this output. And if it's above some

8:53

threshold, we'll call it an agent. I

8:54

don't like thresholds, but you know, we

8:56

just sort of say a degree of agency, a

8:59

degree of sophistication. And coming

9:01

back to Dennit's intentional stance. So

9:03

this is that you know there is um a

9:04

level of representation which serves as

9:06

a useful explanation even though it's

9:08

not actually you know the the the

9:09

microscopic causal graph. And maybe we

9:13

can agree that no agent can possibly be

9:16

the cause of its own actions. But when

9:18

there is a degree of planning

9:20

sophistication

9:21

for you know macroscopically it's as if

9:23

it's the cause of its own actions.

9:25

>> Yes. And that's why this as if phrase

9:27

comes up a lot. Right. I mean this it's

9:29

it's important to remember that like no

9:31

matter how clever your model is and no

9:33

matter how clever your approach is and

9:35

how clever the words are that you use to

9:36

describe it um a lot of this stuff is is

9:39

is as if right this is this is the best

9:43

model right it's not the it's not this

9:45

is why like I I I repeat this over and

9:47

over again

9:49

grind it into the students right is that

9:51

that you know science is about like

9:52

prediction and data compression and like

9:55

nothing else and the same thing is going

9:57

on here right you you'll never, you

9:59

know, just looking at behavior, you'll

10:01

never know for sure in any meaningful

10:04

way like whether or not it's it's just

10:06

doing a function transformation or

10:08

whether it's engaged in planning and

10:09

counterfactual reasoning. But if your

10:11

best model of it, if you sort of say,

10:14

well, I tried to model as a function

10:15

transformation, but god damn it, it had

10:16

a lot of parameters, right? But then I

10:18

tried to model it as something that was

10:19

just doing Monte Carlo research on the

10:21

inside and giving the answer and that

10:23

had like, you know, 40 parameters and

10:24

it's like, well, that's the model I'm

10:26

going to go with and now I'm going to

10:26

call it an agent. If we had a physical

10:29

agent in the real world that was doing

10:31

all of this planning and so on, would

10:33

that have some kind of primacy to a

10:35

computer simulation of agents that were

10:37

doing all of this planning?

10:38

>> Oh, is this is this like uh if I

10:40

uploaded my brain onto a computer and

10:42

didn't connect it to the world, would it

10:43

still be thinking even though it's like

10:45

doing all of those things? Is that the

10:46

idea here or am I like

10:48

>> that works? So, yeah, let's say

10:49

highfidelity computer simulation of

10:51

Jeff. Would would would Jeff be an

10:53

agent?

10:54

>> No. Oh, wasn't expecting you to say that

10:57

>> because I'm the agent and if you uh

11:00

uploaded No, I don't know. Um, so if you

11:04

is do a highfidelity computer simulation

11:05

and you put it in my body, then I think

11:07

I would have to say it's an agent.

11:09

>> Yeah.

11:10

>> Right. If it's doing exactly the same, I

11:12

mean, this is like the standard. It's

11:13

doing exactly the same calculations from

11:15

from a purely like phenomenological

11:16

perspective, it's like it's the same.

11:17

It's indistinguishable.

11:19

>> Okay. So agents need to be physical.

11:21

>> So I do believe that an agent needs to

11:22

be physical. That absolutely. I don't

11:24

believe, you know, I I believe you can

11:26

have a model of agency and not have an

11:28

agent, right? I, you know, you can put

11:30

that model in a computer and run it and

11:32

make predictions as to what an agent

11:34

would do. You and it might even be 100%

11:36

correct, but I still wouldn't call it an

11:38

agent. But again, this is like getting

11:40

into philosophy and like philosophy

11:41

frustrates the basian because philosophy

11:44

is not probabilistic,

11:46

right? [laughter]

11:47

philosophy is really about drawing clear

11:49

lines and distinctions and in my world

11:52

those don't really exist right there's

11:54

everything has an error bar you know all

11:57

of there isn't a clear delineation

11:59

between you know uh you know an object

12:03

and an agent it's really you know in

12:06

from this modeling perspective it's

12:07

really just a question of degrees and

12:09

philosophy is terrible at handling

12:11

questions of degree

12:13

>> my friend Keith he he's a big fan of um

12:15

computability

12:17

and and he thinks that an agent is

12:19

basically you know like a type of

12:21

computation and it has access to ambient

12:25

state and it can take action and there's

12:27

this kind of like cybernetic loop and

12:29

for him the strength of the agency in

12:31

the system is the compute type that the

12:35

thing is doing right so if it's if it's

12:37

a finite state automter then it's a weak

12:39

agent if it's a touring machine it's a

12:41

strong agent

12:42

>> yeah it's the degree of sophistication

12:43

of the compute right

12:45

>> pretty much does That ring true to you?

12:46

>> I mean that if if you were going to make

12:48

if you forced me like, you know, at the

12:51

point of a gun to put a measure on

12:53

agency, it'd probably look a lot like

12:54

that.

12:55

>> Yes. Jeeoff, let's talk about energy

12:57

based models.

12:58

>> Sure.

12:58

>> So, um, Yan Lun, he had a monograph out,

13:01

I think, in 2006 talking about this.

13:03

Been talking about this for a long time.

13:04

>> Oh, yeah. When you fit your neural

13:06

network to data, you know, via gradient

13:08

descent, right? then you have written an

13:11

energy function in weight space and you

13:14

are follow and you're following it to

13:16

its energetic minimum. You know the the

13:18

advantage of using an energy based uh

13:20

taking an energy based approach as

13:21

opposed to taking say a straight up like

13:24

function approximation approach is that

13:25

an energy based model comes with

13:27

something that's kind of like an

13:28

inductive prior right it it basically

13:30

you know an energy based model you know

13:32

if you're just doing function

13:33

approximation you're basically saying

13:34

there's any mapping from x to y x is my

13:36

inputs y any mapping is out there I just

13:38

want to figure out what it is right now

13:40

in an you know in an energy based model

13:42

right you're you're you're you're

13:45

effectively placing constraint s on what

13:48

that input output relationship can be. I

13:50

like thinking about the distinction

13:51

between an energybased model and a and a

13:53

traditional sort of feed forward neural

13:55

network um uh has to do with where your

13:58

cost function is applied. Right? So in a

14:01

in a traditional neural network, you

14:02

take in your inputs, you got your

14:04

outputs, and the cost function is just a

14:06

function of the inputs and the outputs.

14:08

And the only thing that you're

14:08

optimizing is the weights. In [snorts]

14:11

an energy based model, there's another

14:12

thing that that your cost function

14:14

operates on, and that's something one of

14:16

the internal states of your model. And

14:19

as a result like in order to figure out

14:21

what the best you know the the the best

14:22

approach is right you actually have to

14:24

do two minimizations. One that that

14:26

finds the energetic minimum associated

14:28

with the the the part of the cost

14:30

function that operates on the internal

14:32

states like the hidden nodes of your

14:34

network right and then one that is the

14:36

prediction that is your like effective

14:37

prediction error. Um this is this is

14:40

very much consistent with the approach

14:41

that a basian would take right you have

14:43

a you have a a prior probability

14:45

distribution which gives you an energy

14:46

function over every single latent

14:48

variable in your model and you are

14:49

optimizing with respect to all of them.

14:51

So so you take a probabistic approach

14:53

good examples of this are like a

14:54

variational autoenccoder. A variational

14:56

autoenccoder I think is a is the best

14:58

example of the most commonly used

15:00

energybased model out there. Why?

15:01

because you have an encoder network, you

15:03

have a decoder network, right? And your

15:05

cost function is based on the difference

15:07

between inputs and outputs, right? So

15:09

that's just like a that's fine. That's

15:10

still a regular, but it also is how how

15:13

Gaussian in a well, it depends on what

15:15

flavor of V8, but you also have some uh

15:18

some some part of your cost function um

15:21

is a function of the actual rep internal

15:23

representation, right? In a traditional

15:24

VAE, it's it's how Gaussian is. You want

15:27

that internal representation to be as

15:28

Gaussian as possible. Um if it's a VQ

15:31

VAE then it's like mixture of Gaussians

15:33

but it's still like a cost function that

15:35

is applied on the internal states as

15:37

well as on the inputs and outputs.

15:38

>> Very cool. So a VAE is is a fairly

15:40

cononical example of an energy based

15:42

model and what you were saying about the

15:44

I mean you know the whole DL world is

15:46

obsessed with test time inference at the

15:48

moment and in a way that that is a step

15:50

towards what you're talking about. So

15:52

yeah, you're treating a certain Yeah,

15:53

you're treating some of the weights of

15:54

your model, right? I mean, well, yeah,

15:57

you're treating some of the weights of

15:58

your model as if they're latent

15:59

variables, right? Because when you when

16:01

you show a new input, right, you're

16:03

allowed to change some of the weights

16:06

without looking at the output, right?

16:08

And so what are you doing? Well, you're

16:09

treating the weights as latent. Now, I

16:11

think that like which makes it a great

16:13

trick in my opinion. It's like, oh,

16:15

great. Like, yeah, they're they're

16:16

they're they're moving in the direction

16:17

of energy based models. I love it. The

16:19

only thing I don't like about test time

16:20

training is the vast majority of the

16:22

training that is done. So in a

16:23

traditional energy based model, you

16:25

always find the minimum with respect to

16:27

the latent variables, right? These extra

16:28

weights that you know which in this case

16:30

which in the case of test time training

16:31

is the you know the subset of weights

16:33

that you're allowed to to change during

16:35

you know during test time.

16:37

>> Um when you do the training for a

16:39

traditional energy based model, you're

16:41

allowed to make those changes right

16:44

throughout the entire course of

16:45

training.

16:47

The way that we're often doing test time

16:49

training these days is we just do

16:51

regular old neural network learning like

16:53

we don't do and and then and then and

16:55

then finally when it comes to when we

16:56

get to the deployment phase then we

16:58

suddenly turn on right this these

17:01

additional latents which are basically

17:02

some of the weights of the network and

17:04

we do additional an additional bit of

17:06

learning at that point. This seems

17:08

monument. Now again not an expert here

17:10

right but this seems unwise to me and

17:12

the reason it seems unwise is because

17:14

you didn't train the original network

17:15

with that on right you trained it as in

17:18

a completely supervised way

17:20

>> yes

17:20

>> now I'm sure that people have are aware

17:22

of this and it's been addressed in the

17:24

literature but I'm not personally aware

17:26

of that and I don't think that's how

17:28

it's used in practice super

17:29

>> we should also introduce this term

17:31

transduction so my definition of

17:32

transduction is that you're actually

17:34

doing search or optimization as a

17:36

function of the test samples like I

17:38

interviewed Clement Bonnet he had a VAE

17:39

on on arc you know searching latent

17:41

spaces and he actually um searched

17:44

through the decoder as a function of the

17:47

test sample. Yeah

17:48

>> and because these models they are

17:50

maximum likelihood estimators right

17:51

which means they're always giving you a

17:53

kind of smoothed out average and there's

17:55

so much information in the test sample.

17:58

Let's just riff on the relationship

18:00

between energy based models and and

18:02

basian inference. So of course they have

18:04

this advantage that you don't need to do

18:06

this very expensive intractable

18:07

normalization.

18:09

>> Yes.

18:10

>> Yes. Tell me about that.

18:11

>> My take on it is is that an energy based

18:13

model and a basian model have a lot in

18:16

common right in many ways like energy I

18:19

mean well literally in physics right

18:21

energy is like log probab energy is log

18:23

probability. Now of course there's the

18:25

normalization you know factor that you

18:27

don't need to worry about if you're just

18:29

doing if you're just minimizing energy.

18:31

And so the difference between uh you

18:33

know like- which is sort of like you

18:35

know in a basian framework that's like

18:36

saying well you know I'm not actually

18:38

going to treat some of these latent

18:39

variables in a probabilistic way. I'm

18:41

just going to do maximum or map

18:43

estimation on some of my variables and

18:45

just be okay with that. And that's one

18:46

way to interpret the relationship

18:48

between an energybased model and a

18:49

properly basian model. There's there's a

18:52

happy medium here though, right? And the

18:54

happy medium is you can still treat it

18:57

as if it's you know you know you don't

18:59

have to just minimize the energy

19:01

function but you can calculate the

19:02

curvature down there too do a lelass

19:04

approximation and call yourself a basian

19:06

again right yes there is more

19:08

computation involved but we've got a lot

19:09

of great tricks for making that totally

19:11

tractable.

19:12

>> What's the relationship between the free

19:14

energy in the free energy principle and

19:16

the energy and energy based models? uh

19:18

regularization term I think is the short

19:20

answer right um no so so uh the

19:24

difference between an if you're being

19:27

very very very pedantic the difference

19:30

between an energy based you know

19:31

minimizing energy and minimizing free

19:33

energy is that free energy has this

19:35

additional entropy penalty term now if

19:37

you're just doing maximum likelihood

19:38

estimation if you're minimizing your

19:40

energy function with respect to some

19:42

partic well just we'll pretend we're

19:43

only at one variable um and I'm just

19:46

going to like get a point estimate and

19:47

call it a day do like you know some kind

19:49

of map estimation to get to get that

19:50

that one thing there's not that big of a

19:53

difference right because you're you're

19:54

not there is no probability distribution

19:56

over the latent that allows you to

19:58

compute that regularization term but

20:00

that's the only difference it's it's are

20:02

you regularizing or not is I think the

20:05

easiest way to think about it

20:07

>> so lun is a big advocate of jer so these

20:09

joint embedding prediction architectures

20:11

using this non-contrastive learning

20:13

where essentially the the learning

20:15

objective is is comparing the um the the

20:18

the latence of observed and unobserved

20:21

parts of the space. This is an

20:22

architectural design.

20:23

>> Well, what is Okay, so what does Jea

20:25

stand for? It's is it it's joint

20:27

embedding and prediction architecture.

20:30

There we go.

20:31

>> So, what's the joint embedding bit

20:32

about? Well, the joint embedding bit

20:34

about is is, you know, is well, I'm

20:37

going to take my inputs, I'm going to

20:38

take my outputs, and I'm going to embed

20:39

them in some space, right? And then I'm

20:41

going to learn a prediction between the

20:42

two embeddings. And that's a great idea.

20:45

It's a great idea because it has some of

20:46

the flavor of what we would like to get

20:48

out of our models. Like we're not

20:50

interested in predicting every in many

20:52

situations, I should be very particular

20:53

about this. In many situations, we're

20:55

not interested in predicting every

20:56

single pixel on the image. We want to

20:58

get, you know, maybe something that's a

21:00

little more gestalt, a little more high

21:01

level, a little more conceptual

21:02

understanding of what's going on. And so

21:04

emphasizing the goal of predicting every

21:06

single pixel, which is what's typically

21:08

done in generative modeling right now,

21:10

you know, might lose some of the power,

21:12

the abstractive power of some of the

21:13

networks. And so like let's do so so the

21:15

whole point of Japa as I understand it.

21:17

I'm sure there are other points um is

21:19

that uh is that you're going to take

21:21

you're going to you're going to compress

21:23

your inputs and compress your outputs

21:25

and then do all the learning in this

21:26

compressed space. Love it. Right.

21:28

Science is about prediction and data

21:30

compression. Let's make that compression

21:32

explicit on the front end and the back

21:33

end.

21:34

>> The downside of this approach is that is

21:36

it is it it doesn't work out of the box,

21:39

right? Because it's very easy to find a

21:42

compression

21:43

or an embedding of the inputs and an

21:46

embedding of the outputs for which

21:47

prediction is perfect which is to

21:49

basically make both of them zero and so

21:51

you have to do some other things other

21:53

tricks need to be employed in order to

21:55

make it work.

21:56

>> Yes. Yes. I remember Lum was talking

21:58

about this. So there was there's the the

21:59

traditional contrast if method which is

22:02

from it's kind of Hinton's idea

22:03

apparently of like the negative sampling

22:05

and whatnot and and that's very

22:07

expensive because you actually have to

22:09

do lots and lots of sampling and this

22:10

non non-contrastive thing.

22:12

>> Yeah. This is this by the way is what he

22:14

should have won the Nobel Prize for

22:16

>> right [laughter]

22:17

>> in my opinion. Yes. Because the the

22:19

whole point of of of of of the wake

22:21

sleep algorithm and contrasted

22:23

divergence was that oh it's actually

22:25

biologically plausible right it was a it

22:27

was it was an endun around the need to

22:29

do back prop and that's what made it so

22:31

clever and interesting in my opinion.

22:32

>> Lun is a big fan of this non-contrastive

22:35

thing where you work in the the latent

22:37

space. There are many different

22:39

algorithms that do this. We we had a

22:40

whole load of shows all about

22:41

non-contrastive learning. There's things

22:42

like VC Craig and BOL and Barlow twins

22:45

and there's there's an entire thread of

22:47

research all around that and in many

22:49

different ways what they're trying to do

22:50

is avoid this motor collapse problem

22:52

that you're talking about and they use

22:54

different forms of regularization.

22:56

There's an old school way of

22:58

accomplishing the same thing and that is

23:00

that is to to um do all of your is it's

23:03

called pre-processing right and this is

23:06

this is something that a lot of people

23:07

do. take your data and in fact we do

23:09

this all the time with with with like

23:11

vision language models right so we want

23:13

to do we want to use an LLM and we want

23:15

to predict images so what do we do well

23:17

the first thing we have to do is

23:18

tokenize the image

23:19

>> right and so what do we do we run a VA

23:21

we do the pre-processing and we do it by

23:24

is the pre-processing step is completely

23:27

independent

23:29

right from the actual algorithm that's

23:31

going to be the be be tasked with

23:33

solving the problem of interest

23:36

um And you know

23:40

that's not something that

23:43

we necessarily have to stick with,

23:45

right? It would be very nice if there

23:48

was a way of if if there was a way of

23:50

like again well jointly we're getting

23:53

right back to Jeep again. What we'd like

23:55

to do is we'd like to choose our

23:56

pre-processing algorithm in a manner

23:58

that that you know you know not a priori

24:02

not do it first. We like to choose the

24:04

pre-processor that works the best in in

24:06

this space.

24:07

>> Y

24:08

>> and I think that that's the ultimate

24:10

motivation for a lot of this work is

24:11

that there like what's the right

24:12

embedding. One of my favorite tricks

24:15

like of course I you know I pre-process

24:17

with VAS all the time. In fact, it's

24:19

when you know the second every time

24:20

someone hands me a new neural data set,

24:22

the first thing I do and you can I'm I'm

24:25

not ashamed to admit I run PCA on it and

24:28

pass it through a VAE and then sort of

24:29

take a look, right? It's the first thing

24:31

you do with your data because it gives

24:33

you a good idea of what the signal to

24:34

noise ratio is in the data set itself.

24:36

>> Yes.

24:36

>> And then I Yeah. And then what do I do?

24:38

I subsequently do most of my analysis

24:40

right in that discovered embedding

24:43

space. Um, and there's I I I I don't see

24:46

a huge problem with that from a purely

24:48

pragmatic perspective, but it it's

24:51

certainly cleaner, right, to to have a

24:54

single algorithm and approach and not

24:56

just be stringing these sort of things

24:58

together in an ad hoc way. There's, you

25:00

know, when when doing PCA, PCA is a

25:02

really great example of this. There's a

25:03

failure mode for principal component

25:05

analysis, um, which is actually really

25:07

common in neural data because principal

25:09

component analysis basically goes, well,

25:10

where's the most variability? Okay, I'm

25:12

worry about that. And then all the stuff

25:13

that's not varying very much, I'm just

25:14

going to throw it away, right? Just like

25:17

look, you know, dimensions in which

25:18

there's low variability are not

25:19

important. Well, it turns out that in

25:22

neural data, the dimensions in which

25:24

there's very little variability are some

25:26

of the most important dimensions. And so

25:30

pre-processing with PCA runs a risk of

25:32

throwing out the most valuable

25:33

information in your data set.

25:35

>> Yes. And so there's a lot of wisdom in

25:38

in in jointly right pre in in jointly

25:41

fitting your pre-processing model as

25:43

well as your inference and prediction

25:44

model. I mean on this subject of not

25:46

throwing things away um jeoper and

25:49

non-contrasted learning it's part of

25:51

this bigger field of self-supervised

25:53

learning and we want to learn

25:54

representations that maintain fidelity

25:57

and richness and lun's hypothesis is

26:00

that when you do something like

26:01

supervised learning with you know some

26:03

particular downstream task in mind um

26:06

the neural network gets wise and what it

26:08

does is it kind of discards all of the

26:10

the the longtail stuff that aren't

26:12

relevant for that particular task. So

26:14

when you train these models, what you're

26:15

trying to do is sort of maintain enough

26:17

ambiguity so that it it compresses the

26:20

information but it also maintains enough

26:22

fidelity to work broadly for different

26:24

things.

26:24

>> Yes. And that that and that is a lotable

26:27

goal, right? And and I certainly share

26:29

it. Right. The last thing you want to do

26:31

is I mean, you know, fortunately like

26:33

networks are so big, we don't really run

26:34

the risk of of like uh overfitting so as

26:38

much as we used to. Um, but the last

26:40

thing you want to do is throw is is is

26:42

train your network to toss information

26:45

that you might need down the road. Um,

26:48

that said, like the vast majority of

26:49

what you know the brain does just like

26:51

these neural networks is decide what

26:53

information is currently task

26:54

irrelevant. But that's all the more

26:56

reason to do things in a self-supervised

26:58

or unsupervised way, right? Because

27:00

you're basically not telling it this is

27:02

the important, you know, you're not

27:04

telling it like what's all task relevant

27:06

and task irrelevant. So um I interviewed

27:08

Shalet about the version two of the arc

27:11

challenge and one thing that struck me

27:14

is I think of intelligence as being

27:15

multi-dimensional. So version one got

27:18

saturated. The ark was actually really

27:20

amazing because it's the only

27:21

intelligence bench benchmark that has

27:24

survived for 5 years before being

27:25

defeated. You know since the advent of

27:27

these thinking models, it has been

27:29

defeated very quickly. But they're

27:30

working on version three and there'll be

27:32

version four, there'll be version five.

27:35

Will there always just be something left

27:37

over?

27:38

>> That sounds like another philosophical.

27:40

So yes is my answer. There will always

27:43

be there will always be something left

27:45

over in the sense that like you know you

27:47

know we we we have this has been the

27:50

trajectory things have been going for a

27:52

really long time, right? It's sort of

27:53

like we get algorithms that do amazing

27:55

new cool things and then someone comes

27:57

along and says, "Yeah, but it can't

27:58

build me. It can't pull a rabbit out of

28:00

a hat." Right? And then and then of

28:02

course what does someone do? they oh

28:03

they they figure out the new training

28:06

protocol slightly different architecture

28:07

or they just train it to pull rabbits

28:09

out of hats and then suddenly it can and

28:12

then someone proposes a new challenge

28:14

and a new challenge and a new challenge

28:15

and it's always this game of like

28:17

one-upsmanship.

28:18

So the question becomes, well, what's

28:20

the point at which there are no more new

28:21

challenges? And I'm not entirely certain

28:23

we're ever going to get there, right? Um

28:25

it may very well be the case that we

28:27

get, you know, these sort of algorithms

28:29

that are capable of replicating the

28:31

complete suite of human behaviors and

28:32

then someone will come up with some

28:33

criticism like, "Yeah, but it's not

28:36

really doing X. It's just faking it,

28:38

right? This is just the direction things

28:40

go because people really do think

28:41

they're important."

28:42

>> Yeah. Do do you think that the concept

28:44

of recursive self-improving intelligence

28:47

is a valid one? Yes, I do think that is

28:50

so so I think that one of the most

28:51

critical missing elements right now is

28:54

some form of continual learning, right?

28:56

You at the end of the day, you really

28:58

want an algorithm that that doesn't just

29:00

learn on the training that on the

29:01

training set and then just gets

29:03

deployed. You want something that that

29:04

that runs around in the world and comes

29:07

across things that it doesn't

29:08

understand, right? And then is able to

29:11

incorp to build, you know, append its

29:13

model in some sense, right? So this is

29:16

like the this you know and there are

29:18

some approaches to it's all based on

29:19

like basian nonparametrics and dish

29:21

process priors and stuff like that where

29:24

you you sort of see something that's

29:25

surprising or unique or different

29:27

something you didn't expect and it

29:29

causes you to say I need to turn

29:31

learning on because I got to figure this

29:33

out. That is an absolutely critical

29:35

element that we need to be developing.

29:37

We are developing that. And it turns out

29:38

that that's one of the nice things about

29:40

this sort of object- centered physics

29:42

discovery thing is because it's object-

29:43

centered. If it comes across a new

29:45

situation that it does not understand,

29:46

it is capable of instantiating a

29:48

completely brand new object just to

29:50

explain this new situation.

29:52

>> Continually learning agents can acquire

29:54

new knowledge autonomously and and the

29:56

whole you know the whole thing just

29:58

learns more knowledge. But intelligence

30:01

feels different. It it it feels like in

30:04

the system that we've been describing

30:05

the intelligence is the way we're

30:07

implementing the you know the basian

30:09

updates and and you know actually

30:11

building the algorithms. Could could the

30:14

systems on their own meta program

30:16

themselves and develop better algorithms

30:18

or something like that? That's a very

30:20

good question.

30:22

something that would be closer to true

30:23

artificial intelligence than what we

30:25

currently have would be capable of

30:28

building models on the fly to deal with

30:30

new situations to taking things that it

30:32

knows about right and combining them in

30:34

new and different ways. Um uh there are

30:37

approaches that have some of that aspect

30:39

to it. Like GFlow nets from like Benio

30:41

stuff is like is like a great example of

30:44

something that at least in principle is

30:46

a generative model of generative models,

30:48

right? It's sort of like oh like you

30:51

know I might actually need a new node

30:53

like it's time to create a new latent

30:54

variable cuz like like the current set's

30:57

just not cutting the mustard anymore.

30:58

Those are things that that that I think

31:00

are hallmarks of of true intelligence. I

31:02

don't want to ever make the statement as

31:04

soon as it's got that it's truly

31:05

intelligent. I will never ever ever say

31:07

that. Um but I do think that that is a a

31:10

critical component that that needs to be

31:12

present, right? Is the ability to

31:14

generate new models on the fly to deal

31:17

with novel situations and data. Um most

31:20

of that you know um you know as well as

31:24

the ability to um uh combine old models,

31:29

previous models in new and interesting

31:31

ways. This is actually how the brain

31:32

evolved, right? We started out with like

31:35

um you know really simple brains and

31:38

there were different regions and they

31:39

solved sort of different problems and

31:41

what eventually happened as we evolved

31:43

is is that these different regions of

31:45

the brain learned to communicate with

31:47

each other in new ways and through that

31:49

communication acquired new abilities,

31:51

right? And then eventually evolved into

31:53

in you know you know um new capabilities

31:56

and things like that, right? I I often

31:58

like to point out to the the I think

31:59

old-fashioned is like the the sense

32:01

that's not studied nearly enough. It's

32:03

an incredibly old part of the brain. Um

32:05

and arguably, right, it's the it's the

32:08

first part of the brain that evolved the

32:09

ability to do proper like associative

32:11

processing, right? Odor the odor unlike

32:14

visual space, right, where there's

32:16

translation symmetries and and all that

32:18

sort of stuff and things are smooth.

32:19

Alactory space that does not exist,

32:22

right? It's it's really really really

32:24

combinatorial and complicated. And the

32:27

part of the brain that evolved to solve

32:28

the alactory problem arguably is the

32:31

part that evolved into our frontal

32:32

cortex. Don't quote me on that. There's

32:35

a lot of disagreement there. That's just

32:36

my take. Um but it certainly has a lot

32:39

of the features that we associate with

32:40

associative cortex. Right? It is it wow

32:43

I just said got like six uses six three

32:45

different uses of the word associate in

32:47

that sentence. But but I think you see

32:49

what I mean right? It it um it was all

32:52

about like taking old capabilities,

32:55

right? Combining combining, you know,

32:57

simple models and modules to create

32:59

something that was more complex and then

33:01

over time, right? So, so that was what

33:04

made the brain work, right? It was all

33:05

about taking little things that worked

33:07

and combining them in new and different

33:09

ways in order to evolve, you know,

33:11

effectively an emergent, you know,

33:13

emergent properties, emergent, you know,

33:16

computational abilities and an emergent

33:18

understanding of the world in which we

33:20

live. And I do think that like what what

33:22

you know, if when we get to the point

33:24

where we start really saying, oh, this

33:26

is actually truly intelligent, it's

33:28

going to have that feature. It's going

33:30

to have the ability to have a it's going

33:33

to have a modular description of the

33:34

world and it's going to have the ability

33:36

to to combine those modules in a way

33:38

that creates a more sophisticated

33:40

understanding. It's like Legos, right? I

33:42

can, you know, the the Lego bricks all

33:44

connect in certain ways and I can build

33:45

like all sorts of new and amazing things

33:47

that were never built before, right? Out

33:49

of them. That's a capability that we

33:51

have and that's the essence of like

33:53

creativity. It's why I refer to systems

33:54

engineering as like the thing we really

33:57

want our our our AI models to be able to

33:59

do.

34:00

>> Collective intelligence is a bit

34:01

different. We we have this plasticity,

34:04

right? We can adapt our behavior day by

34:06

day. We might see some kind of

34:08

metalarning or some kind of change in

34:10

our organization dynamics. You know,

34:12

maybe some agents will specialize and it

34:14

might be an existence proof of this kind

34:16

of recursive, you know, super

34:17

intelligence that we're talking about.

34:19

>> Yeah, I do. I I I think that's

34:20

absolutely correct. Right. is that you

34:22

know so the specialization is great in

34:24

fact I would argue that specialization

34:26

is how we got all of this right and this

34:28

was I'm pointing at London in case you

34:31

there was some confusion there um right

34:34

it was it was really about you know the

34:36

interconnected highly specialized

34:38

intelligences that are people and their

34:41

ability to learn how to to to work

34:43

together that that that you know gave

34:45

rise to the technological revolution the

34:47

brain is the same way right it's in my

34:50

view it's highly specializ ized little

34:53

modules or agents that are capable of of

34:55

of of

34:57

um being repurposed, reused, um capable

35:00

of communicating with one another in

35:02

order to solve really complicated

35:03

problems. But there's always a benefit

35:05

to specialization. I don't believe in

35:07

like like AGI. AGI seems like a bit of a

35:09

a misnomer to me. What we really want is

35:12

not artificial general intelligent. We

35:14

want collect we want collective

35:15

specialized intelligences.

35:17

>> What about scientific discovery? Do you

35:19

think that we could, you know, what

35:21

would the world look like when we could

35:23

discover new drugs? We could discover

35:24

new knowledge in science.

35:26

>> You know, right now the way that we're

35:27

doing that is is um largely focused on

35:30

summarizing vast troves of data and

35:32

looking for correlations that are

35:33

present in it. Um I think the next major

35:36

milestone um in this trajectory is is

35:40

experimental design, right? Not just oh

35:42

well here's here's some correlations you

35:44

you may not have seen because they're

35:46

really small and this is what computers

35:47

are good at. They're really good at

35:48

identifying small but highly relevant

35:50

correlations. Um and uh the next step of

35:53

course is design is is constructing a

35:56

system that tests these hypotheses

35:58

explicitly right and generates the

36:00

experiments that will identify like that

36:02

will they'll fill in the gaps of our

36:04

knowledge and all of this I believe can

36:06

in fact be automated in a very sensible

36:08

way. I I you know I I don't see any like

36:11

major obstacles to automating empirical

36:13

inquiry other than we probably want to

36:16

place some safety constraints when we

36:17

start letting them work when we start

36:19

letting the AIs run the labs right

36:20

because you never know. So you always

36:22

have this AI was like well you know the

36:24

most effective experiment to determine

36:25

if this is correct is to set off a nuke

36:27

and that that would be bad.

36:29

>> Yes.

36:29

>> Right. So pure empirical inquiry right

36:32

does run risks like that but I think

36:34

that that's not not not the biggest

36:36

issue. I think what we need to do is we

36:38

just had need to have a nice concise

36:39

framework for saying like oh look you

36:41

know like I'll give you an example. So,

36:43

we had this we we we had this um problem

36:45

that popped up a while back. A gentleman

36:48

we were talking to is is um is you've

36:51

got these long, you know, you got these

36:52

robots and the robot sees something it's

36:54

never seen before. And in an I, you

36:56

know, so a robot is like running around.

36:58

It comes across like a beach ball. Never

37:00

seen a beach ball in its entire life.

37:01

And what you'd like is you'd like the

37:03

robot to know how to figure out that

37:05

it's a beach ball and to figure out what

37:07

its properties are. And if you tell the

37:09

robot like like if you see something new

37:11

just stop, right? You're kind of then

37:13

that's that's no good, right? What you

37:15

really want to do is you want to figure

37:17

out a relatively non-invasive procedure

37:19

for the robot to like poke do what a

37:22

child would do. What does a kid do when

37:25

they see a beach ball, right? They run

37:26

up and they poke it and they say, "Oh,

37:28

right. Yeah." And then it moved and and

37:30

it it actually learned it actually

37:31

experiments with its environment for the

37:33

purposes of identifying the properties

37:35

of the objects that exist in it. Um, now

37:38

I do think we probably want to test this

37:39

out virtually before it's deployed in

37:41

the real world because you never know.

37:42

It might very well be that the optimal

37:44

experime experiment is to run up and

37:46

kick it as hard as you possibly can. Um,

37:49

and we we certainly want to avoid that.

37:51

But like something along those lines,

37:52

something, you know, a robot that is

37:53

able to test the theories that it has um

37:57

about how things work in an online way

38:00

and learn from those results in an

38:01

online way is definitely part of the

38:03

goal. Looking forwards, what do you

38:05

think the future will look like when we

38:08

have more autonomous AIs among us? A lot

38:11

of people worry about infeeblement, loss

38:13

of control, you know, it making us dumb,

38:15

all of this kind of stuff.

38:16

>> I do I do worry about AI making us dumb,

38:19

right? I mean, offloading offloading

38:21

your thinking onto a machine, which is

38:23

something that that that that AI allows,

38:26

is is is a potentially a big problem. I

38:30

I don't really want to have a situation

38:31

where humans are reduced to like val

38:34

they're just re reduced to like value

38:36

function selectors. They're just

38:37

basically going, "Oh, no. I don't like

38:38

that outcome. Like do this instead." I

38:40

do want to see a future where where

38:42

where we have an AI that actually

38:44

improves our understanding of the world.

38:46

And simply automating everything runs

38:49

the risk that you specified, right? It

38:50

runs the risk of people becoming couch

38:52

potatoes that just watch TV and

38:53

occasionally say like, "Yeah, you know,

38:56

these chips are no good." Um uh that

38:59

seems like a bad outcome to me.

39:01

>> Um I worry less about that I think than

39:04

some because people are remarkably

39:07

adaptable,

39:08

>> right? I mean I you know you they have

39:10

all these arguments about like oh you

39:12

know this new technology comes along and

39:14

it's going to completely destroy this

39:16

way of life and you know and that's

39:18

going to be awful for people and it is

39:21

maybe in the short term. um you know I

39:23

think of like tractors right or just go

39:25

back how many hundred years do you have

39:26

to go back when like 99% of people were

39:29

involved in agriculture and now it's

39:30

like what two right I consider that a

39:33

solid improvement right because it

39:35

allowed the rest of us to it allowed us

39:37

to do a bunch of other things that we

39:39

find more satisfying that are more

39:41

interesting it allowed us to like you

39:43

know I I can read you know spend some

39:45

time reading a book don't have to labor

39:46

in the fields all day um that's the

39:49

future that I sort of see and that's the

39:50

future that I hope for is that is is one

39:53

in which you know all of these

39:55

artificial agents running around and

39:57

doing things autonomously

40:00

um are there to to free us up to pursue

40:04

more interesting more you know you know

40:06

to improve ourselves in in in in in more

40:09

interesting ways but at the end of the

40:10

day it's just another techn you know at

40:12

least initially it'll just be another

40:13

technology like the tractor um now 100

40:17

years from now who knows

40:18

>> what will the value of work be if the

40:21

AIs can do everything and there's

40:22

nothing left for us to do.

40:23

>> I don't think that it will ever be the

40:25

case that the AIs can do everything.

40:27

Like I said, the future I worry about is

40:28

one where like it's, you know, the the

40:30

sole role of people is like sitting

40:32

around like making sure the AIs aren't

40:34

aren't going rogue and and and things

40:36

like that. Um, which I don't consider a

40:38

good outcome. I would really like to see

40:40

human improvement. You know, I I I

40:42

envision a future of I don't know this

40:45

like cybernetic transhumanism if I'm

40:48

going to go sci-fi on this, right? where

40:50

where you know the technology and us

40:52

evolve together in a way that's

40:54

beneficial for both. That's the goal. Um

40:57

you know are there these dystopic

40:59

possibilities where like oh well what

41:01

are humans in a world where well what

41:03

are they what are what are humans in a

41:05

world where everything can be done by a

41:07

robot.

41:08

>> Yeah. You know, that's that's a good

41:10

question. And that's and at the end of

41:12

the day, right, they end up just

41:15

becoming like reward function selectors,

41:18

right? They end up just sort of saying,

41:19

"Oh, I don't like this and I do like

41:20

that." And they're basically, you know,

41:22

I mean, you end up with a this is

41:24

another nightmare scenario. I don't like

41:26

talking about these dystopian futures

41:27

because honestly I think people are too

41:29

clever and I think people are too

41:31

motivated and people are too interested

41:33

in how the world really works and people

41:35

are too interested in actually

41:36

understanding things that they will

41:38

never stop that they that AI will become

41:41

a partner not an adversary or a crutch

41:44

and that's that's that's what I think

41:46

will happen because that's but that

41:47

that's a statement more about my belief

41:49

about humans than it is about my belief

41:51

about the development of AI you know I

41:53

am a techno optimist if if you will, not

41:56

a not a pessimist. I I believe that we

41:58

will find a way to adapt to an

42:00

everchanging world as we have done for

42:02

millions of years, including one that

42:05

includes technology that alleviates most

42:07

of our labors.

42:09

>> On on that, there's an AI literacy thing

42:11

because AI has moved so quickly now that

42:14

certainly my parents don't understand

42:15

anything about it. But by the same

42:17

token, policy makers don't understand

42:18

anything about it. And there are people

42:21

saying AI is going to kill everyone and

42:22

there's people making negative

42:24

arguments. There's people making

42:25

positive arguments. So, there's a bit of

42:26

a fog of war now because there are so

42:28

many people saying different things

42:29

about AI. How should they make sense of

42:31

all of this?

42:32

>> We are now well outside my area of

42:34

expertise. So, I'm just going to say

42:36

that before I say anything else. Um, AI

42:39

is developing very quickly, but I am

42:42

much more concerned about what people

42:45

will do with the new technology than I

42:47

am with what the technology will do all

42:50

by itself. I don't have the this big

42:53

concern about I don't really believe

42:54

that like you know Skynet's going to

42:56

take over or the internet's going to

42:57

suddenly become conscious and kill us

42:59

all

43:00

>> right um in part because you know AI is

43:04

not that advanced but also because we

43:05

are telling a we you know we are still

43:07

in the position where we specify the

43:09

goals of the system and that will likely

43:14

continue for a very long time and it

43:17

will always be the case that these

43:18

systems you know will can be you

43:21

are are subject to review. We will

43:24

always keep an eye on them. They will

43:26

always at least initially be be released

43:28

in relatively restricted domains and

43:31

where we're where we're test where where

43:32

we're keeping a a close eye on what it

43:34

is that they are and are not doing. So I

43:38

don't worry too much about like the

43:40

going rogue. I worry a lot more about

43:43

somebody

43:45

building, you know, it's sort of like a

43:46

virus which we already have to deal

43:48

with. like somebody builds like some

43:49

insane virus and like takes down the

43:51

internet. I'm more worried about

43:53

malicious human actors than I am

43:55

malicious AI actors because at the end

43:56

of the day all of these algorithms they

43:58

simply do what they are told right we

44:00

train them we tell them here's your

44:02

objective function as long as we are

44:04

specifying the objective function and we

44:06

understand the objective function we're

44:07

probably going to be okay I think the

44:10

safest way to deal with AI concerns is

44:11

to tell people hey look this AI is just

44:14

doing what we told it to we we you know

44:17

we set it up to make really good

44:18

predictions and to achieve these

44:20

outcomes now is it dangerous to like

44:22

specify these outcomes without being

44:24

very very very careful. Yes, it is

44:26

right. That's this is the whole like hey

44:28

Skynet end world hunger and it kills all

44:30

humans. That that's a that is that that

44:32

is a real possibility. But whose fault

44:34

was that? The fault was the person who

44:37

like was very very naively specified

44:39

their goals. There are in fact

44:41

relatively straightforward ways to

44:42

specify the the reward function that

44:45

that don't run that risk nearly as

44:47

badly. And the best one is so are you

44:50

familiar with like maximum entropy

44:51

inverse reinforcement learning? I like

44:53

to call it active inference because it's

44:55

really similar. Um and so there what

44:58

you're doing is you're basically

44:59

observing someone's policy and then

45:00

you're trying to do a maximum entropy um

45:02

model. You're doing maximum model on the

45:05

reward function itself.

45:07

Um at the end of the day what ends up

45:09

happening when you do this is this is

45:11

why it's like basically just like active

45:12

inference. You get a reward fun. So you

45:14

have some you know organism or whatever

45:17

and you're trying to do this for it and

45:18

and it it's got some stationary

45:19

distribution over actions and outcomes

45:21

right it's inputs and outputs of a

45:22

stationary distribution that becomes

45:24

your reward function like not directly

45:26

there's some math involved but basically

45:28

your reward function is a function of

45:29

the steady state distributions over

45:30

actions and outcomes so we could do this

45:32

right we could take the current we could

45:34

take the current manner in which humans

45:36

are making decisions and we could write

45:38

down right what's the stationary what

45:40

what is the current estimate of the

45:41

stationary distribution of our actions

45:43

and outcomes. So this would include

45:44

things like everyone's getting you know

45:45

this number of people are going hungry

45:47

this you know and and you know all the

45:49

stats that describe like the inputs and

45:50

outputs to our policy make you know to

45:52

our policy decision um and then we could

45:55

just ask an AI

45:57

your reward function is the one that

45:59

results in the same outcome that we

46:00

currently have right on average and it

46:04

would execute it and it would and and to

46:05

the extent that it works right it it it

46:08

would it would ultimately result in a in

46:11

an AI algorithm that just sort of is

46:13

like mimicking human behavior, right? Or

46:15

it's at least achieving the same outcome

46:17

that we were achieving before. Now,

46:19

here's the safe way to like improve the

46:21

situation. You don't say end world

46:23

hunger, right? You perturb that

46:25

distribution

46:26

>> over outcomes, right? And just just over

46:30

outcomes a little bit

46:31

>> and then you evaluate the consequences,

46:34

right? It's it's all you're doing. You

46:36

make these little changes in the reward

46:38

in an empirically estimated reward

46:41

function, right? rather than just sort

46:43

of specifying one by hand because that's

46:45

the dangerous thing.

46:46

>> Jeeoff, thank you so much for joining us

46:47

today.

46:47

>> It's my pleasure.

46:48

>> Amazing.

Interactive Summary

The discussion centers on geometric deep learning, agency, and energy-based models. Geometric deep learning is highlighted for its ability to incorporate real-world symmetries like translation and rotation invariance into models. The concept of agency is explored, with a distinction made between a sophisticated object and a true agent, often involving characteristics like planning and counterfactual reasoning. Energy-based models are presented as a powerful tool, offering an inductive prior and constraining input-output relationships, with Variational Autoencoders (VAEs) serving as a prime example. The conversation also touches upon the relationship between energy-based models and Bayesian inference, the challenges of test-time training, and the potential for AI in scientific discovery and automation. The speakers express a techno-optimistic view, believing that AI will ultimately augment human capabilities rather than diminish them, emphasizing adaptability and the potential for human-AI collaboration. Concerns about AI safety are addressed, with a focus on the importance of carefully specifying objective functions and the potential for human actors to pose greater risks than AI itself. The discussion concludes with a reflection on the future of work and human value in an increasingly automated world, emphasizing human adaptability and the pursuit of deeper understanding.

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