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When will computer hardware match the human brain? (1998)

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Re: When will computer hardware match the human brain? (1998)

#52

The estimate for how many operations per second the brain does is quite a wild guess. It starts out very reasonable, estimating the amount of information the eyes feed to the brain. But from there on it's really just a wild guess. We don't know how the brain processes visual input, we don't know what the fundamental unit of processing in the brain is, or if there is one.

It also blows my mind that that, even though DNA seems to just code for proteins and does not store a schematic for a brain in any way that we've been able to decipher so far, human eggs pretty reliably end up growing into people who 9 months after conception already have a bunch of stuff, including visual processing, working. Of course the DNA is not the only input, there is also the mother's body, the whole process of pregnancy, but I don't know how that contributes to the new baby being able to enter the world already intelligent.

It's possible that I'm not aware of some breakthroughs on this topic, though.

Re: When will computer hardware match the human brain? (1998)

#58

The estimate for how many operations per second the brain does is quite a wild guess. It starts out very reasonable, estimating the amount of information the eyes feed to the brain. But from there on it's really just a wild guess. We don't know how the brain processes visual input, we don't know what the fundamental unit of processing in the brain is, or if there is one.

I remember people discovering that the retina neurons were actually in a very non-common and much less connected geometry than most of our neurons, what meant that the numbers on that page were (an unknown number of) orders of magnitude smaller than reality.

But I have no idea what is known nowadays.

Re: When will computer hardware match the human brain? (1998)

#59
post #2

Moravec's plots (from 1998!) are looking more and more like prophecies: https://www.jetpress.org/volume1/power_075.jpg https://www.jetpress.org/volume1/All_things_075.jpg

What I find incredible about the progress of computing power is that there isn't anything that actually makes Moore's law a given. Engineers keep discovering advances in materials science and manufacturing that enable advancements on such a consistent pace. Is this a fluke? Luck? What enables this?

Tens of billions of dollars of investment specifically to keep up with Moore's Law.

It's basically akin to something like the Manhattan Project or the Apollo Program, just something initiated by private corporations rather than a government-directed investment program.

Re: When will computer hardware match the human brain? (1998)

#60
post #3

Moravac (in the linked paper): "In both cases, the evidence for an intelligent mind lies in the machine's performance, not its makeup." Do you agree? I'm much less keen to ascribe "intelligence" to large, pretrained language models given that I know how primitive their training regime is compared to a scenario where I might have been "blended" by their ability to "chat" (double quote here since I know ChatGPT and the…

For reference, I believe relatively rudimentary chatbots have been able to pass forms of the Turing Test for a while, while also being unable to do almost all the things humans can do. It turns out you can make a chatbot quite convincing for a very short conversation with someone you've never met over the internet[1]. I think there's a trend that fooling perception is significantly easier than having the right capabilities. Maybe with sufficiently advanced testing you can judge, but I don't think this is the case in general: in general, our thoughts may be significantly different than we can converse. One obvious example is simply people with disabilities (say a paraplegic) who can't talk at all (while having thoughts of their own): output capability need not necessarily reflect internal capability.

Also, take this more advanced example: if you built a sufficiently large lookup table (of course, you need (possibly human) intelligence to build it, and it would be of impractical size), you can build a chatbot completely indistinguishable from a human that nonetheless doesn't seem like it really is intelligent (or conscious for that matter). The only operations it would perform would be some sort of decoding of the input into an astronomically large number to retrieve from the lookup table, and then using some (possibly rudimentary) seeking apparatus to retrieve the content that corresponds to the input. Your input size can be arbitrarily large enabling arbitrarily long conversations. It seems that to judge intelligence we really need to examine the internals and look at their structure.

I have a hunch that our particular 'feeling of consciousness' stems from the massive interconnectivity of the brain. All sorts of neurons from around the brain have some activity all the time (I believe the brain's energy consumption doesn't vary greatly with activity, so we use it), and whatever we perceive goes through an enormous number of interconnected neurons (representing concepts, impressions, ideas, etc.); unlike typical CPU-based algorithms that process a somewhat large number (potentially 100s of millions) of steps sequentially. My intuition does seem to pair with modern neural architectures (i.e. they could have some consciousness?), but I really don't know how we could do this sort of judgement before understanding better the details of the brain and other properties of cognition. I think this is a very important research area, and I'm not sure we have enough people working on it or using the correct tools (it relies heavily on logic, philosophy and metaphysical arguments; as well as require personal insight from being conscious :) ).

[1] From sources I can't remember, and from wiki: https://en.wikipedia.org/wiki/Turing_test#Loebner_Prize

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