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Comment author: MrMind 09 October 2017 12:16:14PM *  0 points [-]

Am I right to think that this statement is based on the assumption that the brain (and all computation machines) have been proven to have Turing machine equivalents based on the Church-Turing thesis?

No, otherwise we would have the certainty that the brain is Turing-equivalent and I wouldn't have prefaced with "Either the brain is capable of doing things that would require infinite resources for a computer to perform". We do not have proof that everything not calculable by a Turing machine requires infinite resources, otherwise Church-Turing will be a theorem and not a thesis, but we have strong hints: every hypercomputation model is based on accessing some infinite resource (whether it's infinite time or infinite energy or infinite precision). Plus recently we had this theorem: any function on the naturals is computable by some machine in some non-standard time.
So either the brain can compute things that a computer would take infinite resources to do, or the brain is at most as powerful as a Turing machine.

As per the electron thing, there's a level where there is symbolic manipulation and a level where there isn't. I don't understand why it's symbolic manipulation for electronics but not for neurons. At the right abstraction level, neurons too manipulate symbols.

Comment author: Erfeyah 17 October 2017 08:25:08PM 0 points [-]

As per the electron thing, there's a level where there is symbolic manipulation and a level where there isn't. I don't understand why it's symbolic manipulation for electronics but not for neurons. At the right abstraction level, neurons too manipulate symbols.

It is not the symbols that are the problem. It is that the semantic content of the symbol used in a digital computer is observer relative. The circuits depend on someone understanding their meaning. The meaning provided by the human engineer that, since he possesses the semantic content, understands the method of implementation and the calculation results at each level of abstraction. This is clearly not the case in the human brain in which the symbols arise in a manner that allows for intrinsic semantic content.

Comment author: Manfred 05 October 2017 09:58:26PM *  1 point [-]

I think people get too hung up on computers as being mechanistic. People usually think of symbol manipulation in terms of easy-to-imagine language-like models, but then try to generalize their intuitions to computation in general, which can be unimaginably complicated. It's perfectly possible to simulate a human on an ordinary classical computer (to arbitrary precision). Would that simulation of a human be conscious, if they matched the behavior of a flesh and blood human almost perfectly, and could output to you via text channel and output things like "well, I sure feel conscious"?

The reason LWers are so confident that this simulation is conscious is because we think of concepts like "consciousness," to the extent that they exist, as having something to do with the cause of us talking and thinking about consciousness. It's just like how the concept of "apples" exists because apples exist, and when I correctly think I see an apple, it's because there's an apple. Talking about "consciousness" is presumed to be a consequence of our experience with consciousness. And the things we have experience with that we can label "consciousness" are introspective phenomena, physically realized as patterns of neurons firing, that have exact analogies in the simulation. Demanding that one has to be made of flesh to be conscious is not merely chauvinism, it's a misunderstanding of what we have access to when we encounter consciousness.

Comment author: Erfeyah 06 October 2017 07:55:25PM *  0 points [-]

I think people get too hung up on computers as being mechanistic. People usually think of symbol manipulation in terms of easy-to-imagine language-like models, but then try to generalize their intuitions to computation in general, which can be unimaginably complicated.

The working of a computer is not unimaginably complicated. Its basis is quite straightforward really. As I said in my answer to MrMind below “As Searle points out the meaning of zeros, ones, logic gates etc. is observer relative in the same way money (not the paper, the meaning) is observer relative and thus ontologically subjective. The electrons are indeed ontologically objective but that is not true regarding the syntactic structures of which they are elements in a computer. Watch this video of Searle explaining this (from 9:12).”.

Talking about "consciousness" is presumed to be a consequence of our experience with consciousness. And the things we have experience with that we can label "consciousness" are introspective phenomena, physically realized as patterns of neurons firing, that have exact analogies in the simulation.

In our debate I am holding the position that there can not be a simulation of consciousness using the current architectural basis of a computer. Searle has provided a logical argument. In my quotes above I show that the state of neuroscience does not point towards a purely digital brain. What is your evidence?

Comment author: MrMind 06 October 2017 10:21:49AM 0 points [-]

It is that it is not based on syntactic symbol manipulation in the way a computer is and for that reason it is not going to be simulated by a computer with our current architecture (binary, logic gates etc.) as the AI community thought (and thinks).

Well, that would run counter to the Church-Turing thesis. Either the brain is capable of doing things that would require infinite resources for a computer to perform, or the power of the brain and the computer is the same. Indeed, not even computers are based on symbolic manipulation: at the deepest level, it's all electrons flowing back and forth.

Comment author: Erfeyah 06 October 2017 07:44:18PM *  0 points [-]

Well, that would run counter to the Church-Turing thesis. Either the brain is capable of doing things that would require infinite resources for a computer to perform, or the power of the brain and the computer is the same.

Am I right to think that this statement is based on the assumption that the brain (and all computation machines) have been proven to have Turing machine equivalents based on the Church-Turing thesis? If that is the case I would refer you to this article’s section Misunderstandings of the Thesis. If I have understood wrong I would be grateful if you could offer some more details on your point.

Indeed, not even computers are based on symbolic manipulation: at the deepest level, it's all electrons flowing back and forth.

We can demonstrate the erroneous logic of this statement by saying something like: ”Indeed, not even language is based on symbolic manipulation: at the deepest level, it's all sound waves pushing air particles back and forth”.

As Searle points out the meaning of zeros, ones, logic gates etc. is observer relative in the same way money (not the paper, the meaning) is observer relative and thus ontologically subjective. The electrons are indeed ontologically objective but that is not true regarding the syntactic structures of which they are elements in a computer. Watch this video of Searle explaining this (from 9:12).

Comment author: Manfred 04 October 2017 01:09:04AM 1 point [-]

Ah, you mean to ask if the brain is special in a way that evades our ability to construct an analogy of the chinese room argument for it? E.g. "our neurons don't indiviually understand English, and my behavior is just the product of a bunch of neurons following the simple laws of chemistry, therefore there is nothing in my body that understands English."

I think such an argument is totally valid imitation. It doesn't necessarily bear on the Chinese room itself, which is a more artificial case, but it certainly applies to AI in general.

Comment author: Erfeyah 05 October 2017 07:09:39PM *  0 points [-]

Hmm.. I do not think that is what I mean, no. I lean towards agreeing with Searle's conclusion but I am examining my thought process for errors.

Searle's argument is not that consciousness is not created in the brain. It is that it is not based on syntactic symbol manipulation in the way a computer is and for that reason it is not going to be simulated by a computer with our current architecture (binary, logic gates etc.) as the AI community thought (and thinks). He does not deny that we might discover the architecture of the brain in the future. All he does is demonstrate through analogy how syntactic operations work.

In the Chinese gym rebuttal the issues is not really addressed. There is no denial by Searle that the brain is a system, with sub components, through which structure, consciousness emerges. That is a different discussion. He is arguing that the system must be doing something, different or in addition to, syntactic symbol manipulation.

Since the neuroscience does not support the digital information processing view where is the certainty of the community coming from? Am I missing something fundamental here?

Comment author: Erfeyah 03 October 2017 08:07:22PM *  1 point [-]

A few days ago I asked for LW articles regarding the Chinese Room argument and got into a conversation with the user hairyfigment. As I am certainly not convinced of the validity of the Chinese room argument myself I tried to understand the Chinese gym extension of the argument and if/why it matters to the original point. In particular I pointed to the relevance of the brain not evidently being a digital computer. I went back to the 2014 book The Future of the Brain: Essays by the World's Leading Neuroscientists which is a recent exposition of our current (quite poor) understanding of the brain. In particular I went back to the chapter The Computational Brain by Gary Marcus. Here are some quotes that I believe are relevant. Unfortunately I can not provide the full chapter for copyright reasons but I do recommend the book.

[...] we still haven't even resolved the basic question of whether brains are analog, digital, or (as I suspect but certainly can't prove) a hybrid of the two.

and

Going hand in hand with the neural network community's odd presumption of initial randomness was a needless commitment to extreme simplicity, exemplified by models that almost invariably included a single neuronal type, abstracted from the details of biology. We now know that there are hundreds of different kinds of neurons , and the exact details—of where synapses are placed, of what kinds of of neurons are interconnected where-make an enormous difference. Just in the retina (itself a part of the brain), there are roughly twenty different types of ganglion cells; there, the idea that you could adequately capture what's going on with a single kind of neuron is absurd. Across the brain as a whole, there are hundreds of different types of neurons, perhaps more than a thousand, and it is doubtful that evolution would sustain such diversity if each type of neurons were essentially doing the same type of thing.

Is the non or partially digital nature of the brain relevant to certain arguments based on neural networks presented in the sequences?

Does it open the possibility that Searle's argument on syntactic symbol manipulation might be relevant?

Apart from the digital/analog point what about the neural complexity and variety? What if anything does it show about the current state of AI research?

Comment author: hairyfigment 18 September 2017 07:48:14PM 0 points [-]

I repeat: show that none of your neurons have consciousness separate from your own.

Why on Earth would you think Searle's argument shows anything, when you can't establish that you aren't a Chinese Gym? In order to even cast doubt on the idea that neurons are people, don't you need to rely on functionalism or a similar premise?

Comment author: Erfeyah 18 September 2017 10:21:14PM *  0 points [-]

(I am not sure at all about all this so please correct me if you recognise any inconsistencies)

First of all, I honestly don't understand your claim that neurons have consciousness separate from our own. I don't know but I surely don't have any indication of that...

Why on Earth would you think Searle's argument shows anything, when you can't establish that you aren't a Chinese Gym?

The point is that the brain is not a Touring machine since it does not seem to be digital. A Chinese Gym would still be a syntactic system that uses 'instructions' between people.This is related to the way Giulio Tononi is attempting to solve the problem of consciousness with his Phi theory.

Comment author: hairyfigment 18 September 2017 08:58:15PM 0 points [-]

The second set of brackets may be the disconnect. If "their" refers to moral values, that seems like a category error. If it refers to stories etc, that still seems like a tough sell. Nothing I see about Peterson or his work looks encouraging.

Rather than looking for value you can salvage from his work, or an 'interpretation consistent with modern science,' please imagine that you never liked his approach and ask why you should look at this viewpoint on morality in particular rather than any of the other viewpoints you could examine. Assume you don't have time for all of them.

If that still doesn't help you see where I'm coming from, consider that reality is constantly changing and "the evolutionary process" usually happened in environments which no longer exist.

Comment author: Erfeyah 18 September 2017 09:21:28PM *  0 points [-]

If "their" refers to moral values, that seems like a category error. If it refers to stories etc, that still seems like a tough sell.

Could you explain in a bit more detail please?

Rather than looking for value you can salvage from his work, or an 'interpretation consistent with modern science,' please imagine that you never liked his approach and ask why you should look at this viewpoint on morality in particular rather than any of the other viewpoints you could examine. Assume you don't have time for all of them.

No I do see where you are coming from and I don't blame you at all. But do see that you are not addressing the actual argument, in its proper depth. My problem becomes one of convincing you to give your attention to it. Even then it would be difficult to accept an approach that is based on a kind of lateral thinking that requires you to be exposed to multiple patterns before they connect. It is a big problem that I alluded to when I wrote my post Too Much Effort | Too Little Evidence. Peterson is trying to create a rational bridge towards the importance of narrative structures so that they are approached with seriousness.

If that still doesn't help you see where I'm coming from, consider that reality is constantly changing and "the evolutionary process" usually happened in environments which no longer exist.

This is addressed. The most archetypal stories are universal at all times and places. Other ones are modified according to time, place and people. Even the process and need of modification is encoded inside the stories themselves. These are extremely sophisticated systems.

Comment author: hairyfigment 18 September 2017 08:11:19PM 0 points [-]

Without using terms such as "grounding" or "basis," what are you saying and why should I care?

Comment author: Erfeyah 18 September 2017 08:35:14PM 0 points [-]

Good idea, let me try that.

I am pointing to his argument on our [communication] of moral values as cultural transmission through imitation, rituals, myth, stories etc. and the [indication of their correspondence with actual characteristics of reality] due to their development through the evolutionary process as the best rational explanation of morality I have come across.

And you should care because... you care about truth and also because, if true, you can put some attention to the wisdom traditions and their systems of knowledge.

Comment author: hairyfigment 18 September 2017 06:01:42AM *  0 points [-]

What about it seems worth refuting?

The Zombie sequence may be related. (We'll see if I can actually link it here.) As far as the Chinese Room goes:

  • I think a necessary condition for consciousness is approximating a Bayesian update. So in the (ridiculous) version where the rules for speaking Chinese have no ability to learn, they also can't be conscious.
  • Searle talks about "understanding" Chinese. Now, the way I would interpret this word depends on context - that's how language works - but normally I'd incline towards a Bayesian interpretation of "understanding" as well. So this again might depend on something Searle left out of his scenario, though the question might not have a fixed meaning.
  • Some versions of the "Chinese Gym" have many people working together to implement the algorithm. Now, your neurons are all technically alive in one sense. I genuinely feel unsure how much consciousness a single neuron can have. If I decide to claim it's comparable to a man blindly following rules in a room, I don't think Searle could refute this. (I also don't think it makes sense to say one neuron alone can understand Chinese; neurologists, feel free to correct me.) So what is his argument supposed to be?
Comment author: Erfeyah 18 September 2017 06:16:27PM 0 points [-]

Thanks for the pointer to the zombie sequence. I 've read part of it in the past and did not think it addressed the issue but I will revisit.

What about it seems worth refuting?

Well, the way it shows that you can not get consciousness from syntactic symbol manipulation. And Bayesian update is also a type of syntactic symbol manipulation so I am not clear why you are treating it differently. Are you sure you are not making the assumption that consciousness arises algorithmically to justify your conclusion and thus introduce circularity in your logic?

I don't know. Many people are rejecting the 'Chinese room' argument as naive but I haven't understood why yet so I am honestly open to the possibility that I am missing something.

Comment author: fortyeridania 18 September 2017 02:22:38AM 1 point [-]

I don't remember if the Sequences cover it. But if you haven't already, you might check out SEP's section on Replies to the Chinese Room Argument.

Comment author: Erfeyah 18 September 2017 06:06:31PM 0 points [-]

That is great! Thanks :)

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