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Why Robot Brains Need Symbols

nautil.us

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Re: Why Robot Brains Need Symbols

#11

Post by ben_w »

opless wrote: post #9

He's right about LeCun. Yann really does not like Deep Learning being criticized. Please someone who knows much more than me about deep learning tell me how a deep learning ai can explain how it came to an answer. It can't. By definition. You can say that it's a equation with a lot of terms, but that isn't really showing your working out. You need a symbolic system to show that working out. This isn't to say that dee…

> Please someone who knows much more than me about deep learning tell me how a deep learning ai can explain how it came to an answer.

> It can't. By definition.

What definition are you using?

From the my understanding, if you can explain your reasoning, then a deep learning system can in principle learn how to explain its reasoning. If it couldn’t, you couldn’t either.

Re: Why Robot Brains Need Symbols

#12

Post by laichzeit0 »

I really don't get Gary Marcus' fundamental problem. He ends the essay with "All I am saying is to give Ps (and Qs) a chance.". But who exactly is this aimed at? Surely no one is being held academically ransom to Deep Learning. If Ps (and Qs) is a better approach then do the research and publish the results. Instead he just seems to whine about it on Twitter all day and attack people who are actually "doing the research and publishing the results."

Re: Why Robot Brains Need Symbols

#13

Post by chimprich »

317070 wrote: post #2

No, they don't. Now, feel free to _show_ me that they do, and I will gladly accept to have been wrong. But this argument that because of some very theoretical view on the problem the current engineering solutions should be abandoned, without actually providing good engineering alternatives, is weird. I have a bit of a "not even wrong" feeling on the symbolist side of the debate. Deep neural networks have serious flaw…

> But this argument that because of some very theoretical view on the problem the current engineering solutions should be abandoned

That's not the author's argument at all. Even the subtitle of the article says "We’ll need both deep learning and symbol manipulation to build AI.".

Re: Why Robot Brains Need Symbols

#14

Post by opless »

ben_w wrote: post #11
opless wrote: post #9

He's right about LeCun. Yann really does not like Deep Learning being criticized. Please someone who knows much more than me about deep learning tell me how a deep learning ai can explain how it came to an answer. It can't. By definition. You can say that it's a equation with a lot of terms, but that isn't really showing your working out. You need a symbolic system to show that working out. This isn't to say that dee…

> Please someone who knows much more than me about deep learning tell me how a deep learning ai can explain how it came to an answer. > It can't. By definition. What definition are you using? From the my understanding, if you can explain your reasoning, then a deep learning system can in principle learn how to explain its reasoning. If it couldn’t, you couldn’t either.

We're not deep learning systems. So reasoning by analogy there isn't correct.

(Aside: There have been experiments that show that many explanation for [everyday] actions are, in fact made up after the decision to execute an action. Which gives some insight to the whole nature of free will - but that's another discussion entirely. However, indeed we're able to show our workings for higher level workings, like mathematical proofs. )

Deep learning systems, are examples of supervised learning. Once trained, they cannot adapt to new input. You have to retrain to accommodate new features that you want to capture.

Deep learning systems, are in essence a very long equation that hides all meaning over the entire network - good luck in finding out why it came to a decision. You might get lucky and see a definitive triggering path through the network, but that's an exception to the rule, as far as I understand. (I'm willing to be proven wrong here.)

Symbolic systems, can trivially be made to trace the code execution paths they made for any action they might take.

(also - hi Ben! I recognise your blog!)

Re: Why Robot Brains Need Symbols

#15

Post by Symmetry »

ben_w wrote: post #11
opless wrote: post #9

He's right about LeCun. Yann really does not like Deep Learning being criticized. Please someone who knows much more than me about deep learning tell me how a deep learning ai can explain how it came to an answer. It can't. By definition. You can say that it's a equation with a lot of terms, but that isn't really showing your working out. You need a symbolic system to show that working out. This isn't to say that dee…

> Please someone who knows much more than me about deep learning tell me how a deep learning ai can explain how it came to an answer. > It can't. By definition. What definition are you using? From the my understanding, if you can explain your reasoning, then a deep learning system can in principle learn how to explain its reasoning. If it couldn’t, you couldn’t either.

Humans can almost always give an explanation judgement but, for intuitive judgements at least, the reasons we give are frequently wrong or incomplete. People seldom notice that we rate essayists with more symmetric faces as better at writing but we have this bias and tons more besides.

But I don't think that there's any reason to doubt that when using abstract reasoning, Kahneman's system 2, our explanations of our thought processes can't be accurate. It's system 1 that's opaque to accurate introspection.

Re: Why Robot Brains Need Symbols

#16

Post by szemet »

Symmetry wrote: post #15
ben_w wrote: post #11

Earlier quoted context omitted.

> Please someone who knows much more than me about deep learning tell me how a deep learning ai can explain how it came to an answer. > It can't. By definition. What definition are you using? From the my understanding, if you can explain your reasoning, then a deep learning system can in principle learn how to explain its reasoning. If it couldn’t, you couldn’t either.

Humans can almost always give an explanation judgement but, for intuitive judgements at least, the reasons we give are frequently wrong or incomplete. People seldom notice that we rate essayists with more symmetric faces as better at writing but we have this bias and tons more besides. But I don't think that there's any reason to doubt that when using abstract reasoning, Kahneman's system 2, our explanations of our t…

Aren't we - as a group - better in this? I'm thinking about the scientific method, and the common differentiation there between the context of discovery and the context of justification.

So you are free to discover a mathematical theorem by intuition or during daydreaming (like the molecular structure of benzene) - anything goes.

But in the context of justification, you have to be much more disciplined - even if you trust your own intuitions and don't need to persuade yourself (of course generally you should not trust your intuition in scientific context that much;), you have to persuade others who are missing your insight.

edit: And of course - in the end - to accept something as a true A.I. system, it probably has to persuade us that its intuitions are right, using the type justifications we accept. (So even if it has better types of justification - if we won't get it, they has to dumb it down to our level of scientific understanding)

Re: Why Robot Brains Need Symbols

#18

Post by [deleted] »

laichzeit0 wrote: post #12

I really don't get Gary Marcus' fundamental problem. He ends the essay with "All I am saying is to give Ps (and Qs) a chance.". But who exactly is this aimed at? Surely no one is being held academically ransom to Deep Learning. If Ps (and Qs) is a better approach then do the research and publish the results. Instead he just seems to whine about it on Twitter all day and attack people who are actually "doing the resea…

[deleted]

Re: Why Robot Brains Need Symbols

#19

Post by FakeComments »

opless wrote: post #14
ben_w wrote: post #11

Earlier quoted context omitted.

> Please someone who knows much more than me about deep learning tell me how a deep learning ai can explain how it came to an answer. > It can't. By definition. What definition are you using? From the my understanding, if you can explain your reasoning, then a deep learning system can in principle learn how to explain its reasoning. If it couldn’t, you couldn’t either.

We're not deep learning systems. So reasoning by analogy there isn't correct. (Aside: There have been experiments that show that many explanation for [everyday] actions are, in fact made up after the decision to execute an action. Which gives some insight to the whole nature of free will - but that's another discussion entirely. However, indeed we're able to show our workings for higher level workings, like mathemati…

I don’t think we’re able to show our workings for higher level things like proofs.

For instance, I can’t tell you (accurately) how I composed the proof conceptually, ie what strategy it takes, or even determined the appropriate steps, ie how I determined to use a particular tactic.

I can tell you the premises lead to the conclusion via a chain of reasoning, but that’s the artifact of my thought process, not anything about how it works. The output of proving is that chain of steps.

So I think here is somewhere DL systems may have an advantage: they actually can freely introspect their thought process as part of their thought process.

Re: Why Robot Brains Need Symbols

#20

Post by Eridrus »

laichzeit0 wrote: post #12

I really don't get Gary Marcus' fundamental problem. He ends the essay with "All I am saying is to give Ps (and Qs) a chance.". But who exactly is this aimed at? Surely no one is being held academically ransom to Deep Learning. If Ps (and Qs) is a better approach then do the research and publish the results. Instead he just seems to whine about it on Twitter all day and attack people who are actually "doing the resea…

Gary isn't a technologist, but he wants to set the stage with critique so that when/if a fusion of the ideas does better he can claim to have been important to that, regardless of the fact that the idea is obvious, and the implementation is what is hard
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