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Single cortical neurons as deep artificial neural networks

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Re: Single cortical neurons as deep artificial neural networks

#121

Earlier quoted context omitted.

I understand your points, but it's important to understand that humans ARE Turing Machines. We don't know of anything that CAN be computed bit can't be computed by a Turing Machine, so General AI would be a Turing Machine. The Turing Machine model is specifically designed to abstract what a human (mathematician) does: you have a notebook (tape) and some kind of working memory inside your head, and at any one time you…

The problem for me with that line of reasoning is that it's one based on philosophy & not mathematically proven or with any clear evidence. For example, [1], [2], [3] all show there are classes of computation outside of Turing machines. So if we agree there are computations outside of Turing machines, then the question is where does the human brain fall and, relatedly, can non-Turing machines run Turing machines? I s…

I do not have access to the third paper, which may hold somewhat more interest. Otherwise, all examples of models of hypercomputation in [1] and [2] are relying on performing an infinite number of steps in a finite time OR on precisely knowing the solution to an uncomputable problem. These are as interesting as trying to solve human flight assuming anti-gravity exists - they are obviously non-physical, absurdist models.

In fact, we don't know of a single physical process that is not Turing Computable, at least if we add randomness. Even with quantum wave-function collapse, we already know that QCs are still Turing equivalent.

This all suggests to me that the prior for the human mind being Turing equivalent can only be taken to be very close to 1.

Re: Single cortical neurons as deep artificial neural networks

#122
post #20

Earlier quoted context omitted.

Also, sensations and feelings are not a logical/mathematical byproduct of the neurons; no matter how "well" you simulate "neurons", feelings and sensations will not emerge.

Unless you believe in a transcendent soul that could be the source of these sensations or feelings, this assertion doesn't make sense. Assuming there is no supernatural soul, it's logically impossible for anything humans experience to not arise from the human body. This entire notion of qualia is a philosophical quagmire predicated on the idea that if you can imagine something, it must be true ("we can imagine a zomb…

There is no need for a "soul" to produce qualia.

You just need biological machinery and computers are not biological machinery capable of producing sensations.

The phenomena itself is not the same as the description of the phenomena, or a model/simulation.

No matter how well the model predicts the phenomena, it is still not the same thing.

But my postulation was that the simulation won't even be that good because we're still missing so much information.

Further, even IF we could "simulate" every quantum particle itself, the simulation would not be the same thing.

Re: Single cortical neurons as deep artificial neural networks

#123
post #35
post #20

Earlier quoted context omitted.

Also, sensations and feelings are not a logical/mathematical byproduct of the neurons; no matter how "well" you simulate "neurons", feelings and sensations will not emerge.

I don't think we have the faintest clue what subjective experience of self (whatever you call it, qualia?) actually is, to be able to say it isn't artificially reproducible.

We know that computers are absolutely not the kind of machinery to produce sensations.

We know non-biological organisms don't produce qualia.

We know it involves chemical reactions, because we can change qualia with drugs.

Re: Single cortical neurons as deep artificial neural networks

#124

Earlier quoted context omitted.

It might only be wrong for programs that have never existed and will ever exist.

Sure, that's possible, but the opposite is also possible: it might be wrong for most programs we actually write. Well, to be fair, there is some upper bound for any program running on a real CPU.

>Sure, that's possible, but the opposite is also possible: it might be wrong for most programs we actually write.

We could confirm this though! It's not like we can't find out if a given program halts or is inconsisent. Godel talks about it in his letter to Von Nuemann.

Re: Single cortical neurons as deep artificial neural networks

#125
post #100
post #63

Earlier quoted context omitted.

Indeed. Building an AI that matches human intelligence using equal or less mass than a human brain requires one or both of two things to be true: 1. The computational mass efficiency of brain tissue is very far from optimum. Considering the amount of time evolution has been improving upon it, I highly doubt that is true. 2. Most of the brain's computation is not involved in cognition. That may be true. We don't reall…

I think the idea that brain tissue is near optimally efficient is interesting. Yes, it's had a long time to evolve. But the same can be said about photosynthesis which is less efficient at capturing solar energy than PVs. The evolution of brain tissue was under constraints about something that could be made by biological systems from the resources we could eat. Is it not plausible that some very efficient computation…

But the same can be said about photosynthesis which is less efficient at capturing solar energy than PVs.

The instantaneous efficiency is much lower, sure, but the lifetime efficiency is another question. The resource cost to create a plant is the nutrient/energy cost of producing and dispersing a seed. The energy cost of producing and installing a solar panel is enormous by comparison, and takes years if not decades to capture more resources than it took to produce.

Home solar panels capture 11-15% of incoming energy. Plant leaves capture 3-6%. Do you have solar panels now? If you could throw five dollars in seeds over your roof and get half that amount of electricity, would you?

Re: Single cortical neurons as deep artificial neural networks

#126
post #122

Earlier quoted context omitted.

Unless you believe in a transcendent soul that could be the source of these sensations or feelings, this assertion doesn't make sense. Assuming there is no supernatural soul, it's logically impossible for anything humans experience to not arise from the human body. This entire notion of qualia is a philosophical quagmire predicated on the idea that if you can imagine something, it must be true ("we can imagine a zomb…

There is no need for a "soul" to produce qualia. You just need biological machinery and computers are not biological machinery capable of producing sensations. The phenomena itself is not the same as the description of the phenomena, or a model/simulation. No matter how well the model predicts the phenomena, it is still not the same thing. But my postulation was that the simulation won't even be that good because we'…

> You just need biological machinery and computers are not biological machinery capable of producing sensations.

This is a postulate, not an argument. My contention is that qualia are meaningless - like saying that there is such a thing as "feeling like you're computing the number 1000" for a processor, or "feeling like you are a really hard granite" for a piece of granite. Just because we can express it doesn't mean that it makes sense.

All of the conundrums about qualia go away if we just accept this. Alice would not in fact experience anything new when she saw red for the first time, if she knew everything about human cognition and the physical properties of the color red.

I do absolutely agree that we know almost nothing about how these processes actually happen in the brain, and most attempts at AI and bombastic predictions about replacing humans are off the mark by centuries. But that is no reason to assume that there is something completely different going on in animal brains than computation, in the wide sense of the Turing machine model.

Re: Single cortical neurons as deep artificial neural networks

#127

Earlier quoted context omitted.

Sure, that's possible, but the opposite is also possible: it might be wrong for most programs we actually write. Well, to be fair, there is some upper bound for any program running on a real CPU.

>Sure, that's possible, but the opposite is also possible: it might be wrong for most programs we actually write. We could confirm this though! It's not like we can't find out if a given program halts or is inconsisent. Godel talks about it in his letter to Von Nuemann.

There are programs for which we can check this, but there is no general procedure to check if any program halts. Even ignoring the halting problem itself, say we analyze a program and realize it halts iff P=NP, or pi to the e is transcendental, .or if Pi's decimal expansion at position Graham's number is divisible by 3. Will that program halt? It might be very hard to say.

More promisingly, there are ways to construct programs such they will halt, using total languages (though not every problem can be solved with such a limitation).

Re: Single cortical neurons as deep artificial neural networks

#128
post #117
post #59

Earlier quoted context omitted.

Wouldn't it suck if brains are just reservoirs used by the internet that can store roughly 3 memes at a time?

holds up a Duracell battery "You think thermodynamics means using humans as batteries is a dumb idea? Where do you think you learned thermodynamics?" faint nyan cat music in the background

"May I have a physics textbook?" "No. The real world doesn't run on math."

Re: Single cortical neurons as deep artificial neural networks

#129
post #122

Earlier quoted context omitted.

There is no need for a "soul" to produce qualia. You just need biological machinery and computers are not biological machinery capable of producing sensations. The phenomena itself is not the same as the description of the phenomena, or a model/simulation. No matter how well the model predicts the phenomena, it is still not the same thing. But my postulation was that the simulation won't even be that good because we'…

> You just need biological machinery and computers are not biological machinery capable of producing sensations. This is a postulate, not an argument. My contention is that qualia are meaningless - like saying that there is such a thing as "feeling like you're computing the number 1000" for a processor, or "feeling like you are a really hard granite" for a piece of granite. Just because we can express it doesn't mean…

Qualia is not meaningless because we are nothing without it.

Take sensations away and you turn into a vegetable in a couple of hours -- see solitary confinement, isolation tanks and so on.

Re: Single cortical neurons as deep artificial neural networks

#130

Earlier quoted context omitted.

The problem for me with that line of reasoning is that it's one based on philosophy & not mathematically proven or with any clear evidence. For example, [1], [2], [3] all show there are classes of computation outside of Turing machines. So if we agree there are computations outside of Turing machines, then the question is where does the human brain fall and, relatedly, can non-Turing machines run Turing machines? I s…

I do not have access to the third paper, which may hold somewhat more interest. Otherwise, all examples of models of hypercomputation in [1] and [2] are relying on performing an infinite number of steps in a finite time OR on precisely knowing the solution to an uncomputable problem. These are as interesting as trying to solve human flight assuming anti-gravity exists - they are obviously non-physical, absurdist mode…

That’s a solid counter argument. I assume you’re saying we don’t know of a single physical process that’s not a Turing machine because all of the models we have built to simulate them are Turing computable? That’s a strong point. Maybe I should readjust my prior on this. It does sound like you’re better versed in this topic. I like to learn by asking questions, so if you’re amenable to answering please do. If you don’t, then please don’t. It can be overwhelming for some and I’m not trying to prove you wrong. I admit I rushed into a position in haste without actually being well prepared on the topic and had way too much confidence in my own opinion.

I have some devil’s arguments but maybe they’re all bad. Genuinely, my technical grounding and knowledge here has atrophied to (at least I feel like) extremely laughable point and didn’t start high to begin with as undergrad engineering teaches a very different kind of math and I really limited my extracurricular need to seriously study beyond the core engineering topics. Even there, doing the bare minimum to just cram through exams rather than actually learning and understanding the topics throughout the year.

If we have only very primitive models of how the world works. After all we can simulate how the smallest atoms work to maybe some more complicated chemical interactions. Still, as it gets to biology our ability to simulate things breaks down rapidly. I don’t mean at a performance level, but at a “we’re waaaaaaay off in the applied aspects”. Drug discovery is one I’m thinking of. Or predicting someone’s facial features from their DNA (that last one always feels extremely dubious but news friendly). Or general AI. Those have seem to hit a wall in results. That’s close to a god of the gaps argument so let me know if that’s a bad faith one because that’s just too small a gap for non computability to live vs we just aren’t smart enough yet as a species? I could see that.

Or what about that we don’t know of any actually infinite Turing machines at a physical level (thermodynamics and heat death off the universe puts an upper bound there I am thinking now randomly to justify my position rather than considering that before-hand). So is anything really a Turing machine in reality or are Turing machines themselves just a useful tool/model to model the universe but not 100% accurate and the world works slightly differently and the error comes from non computability and not randomness? Let me know if that’s just a kooky supposition on my part in case the math of Turing machines already proves that non-infinite things are always Turing computable and is very basic results I have forgotten/never learned.

What if the Turing machine model is an easy tool to simulate parts of it but not possible to simulate the thing itself? Like the universe itself is not computable on a Turing machine. As far as I know something like that’s been proven in the past few years - there was a proof that if we are living in a simulation, then the physical rules of the thing running the simulation would have to be very different and not look like our universe. Doesn’t that indicate that there’s a limit to the size of any Turing machine we could build to model the universe itself, and thus maybe the infinite model required to build a theoretical Turing machine itself doesn’t map to how reality works. I’ll admit freely this one may have an improper grounding in Turing machines even at a popular level as I only read the abstract to that paper and maybe I misread it or I’m misremembering something that has so much technical nuance that I’m missing what that actually means and misremembering.

Has it been investigated on the theoretical side whether the interaction of networks of Turing machines (whether intelligent or not) all interacting is itself Turing computable? Would that simulation itself be an instance of hypercomputation or some other non computable area of research? I don’t understand the basics well enough to interpret that research so I’m hoping you do. I started reading the Wikipedia article and my eyes just glazed over.

I would think these would all be very significant problems but I’ve admittedly not kept up on my understanding of how this stuff works at a deep mathematical level (and have let those skills atrophy over the years) and maybe that’s all been answered or I have significant flaws in my intuition. I really and sincerely appreciate you taking the time to respond and explain and talk about this stuff. I don’t like studying but I love learning what the higher level intuitions are of people who do study this stuff more deeply are.

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