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I used to think there must be something 'special' to brains to distinguish us from computers. There isn't. Brains encode finite amounts of information (quantum

I used to think there must be something 'special' to brains to distinguish us from computers. There isn't. Brains encode finite amounts of information (quantum mechanics seems to imply bounded local information). We are a huge information network ourselves -- that's what consciousness is (with some added bits like self-identity and various particulars structures that dictate the character of our experience). But that doesn't mean brains aren't special -- it means brains are special and computers are special. Even more: it seems to imply computers, AI, etc. can be as special as ourselves, sentient, and perhaps even more special in ways we haven't realized yet. It's difficult to even imagine a physical theory with unbounded local information. It seems to open the possibility to crazy things like hypercomputation, which do not seem very well defined. (For example: every 1-1/n seconds, (n>1) from now, flip a switch ON/OFF. At what state will the switch be at t>1s? An at exactly t=1s?) Note: while information and information flow itself bounded (hence no hypercomputation), I don't know of any obvious objections to continuous time. (I'm not sure the continuity of time has any profound implications)

mjburgess 5y ago
the issue isn't brains no algorithm running on a cpu can move a muscle -- it is precisely that movement is a spatiotemporal property which means no turing machine can realise it movement isn't a symbolic operation
- tsimionescu 5y ago
  This is such a strange claim to make, I can't even tell what you could have meant. We are surrounded by simplistic mechanical computations moving muscles , and have been for more than a hundred years, since the industrial revolution at least.
- gnramires 5y ago
  What do you suppose those computers are doing, then? ;) https://www.youtube.com/watch?v=tF4DML7FIWk https://www.youtube.com/watch?v=tF4DML7FIWk https://www.youtube.com/watch?v=tfb6aEUMC04&t=115s https://www.youtube.com/watch?v=tfb6aEUMC04&t=115s
  - PeterisP 5y ago
    I would go a step further and look at the research on medical devices for spinal-damage patients which try to literally control their existing muscles through a computer; the concept of neuroprosthesis and https://en.wikipedia.org/wiki/Functional_electrical_stimulation https://en.wikipedia.org/wiki/Functional_electrical_stimulat... working to design algorithms on CPU to move muscles, as the parent post words it.
- ineedasername 5y ago
  In this very narrow sense that you are defining, no brain can move a muscle either. All it can do is send signals. A computer can do the same. If you are making a broader claim about the limits of hardware vs. wetware the you will need to clarify things a bit further.
eru 5y ago
> It's difficult to even imagine a physical theory with unbounded local information. It seems to open the possibility to crazy things like hypercomputation, which do not seem very well defined. (For example: every 1-1/n seconds, (n>1) from now, flip a switch ON/OFF. At what state will the switch be at t>1s? An at exactly t=1s?) I agree with the latter, but the former? Classical Newtonian mechanics is easy enough to imagine. What baffles me a bit is that quantum mechanics seems to be linear, but we seem to see chaos in the real world. (And exactly that (mathematical) chaos is also what the article exploits.)
- istjohn 5y ago
  Chaos arises in very simple (Newtonian) systems, e.g. the double pendulum[1]. 1. https://en.m.wikipedia.org/wiki/Double_pendulum https://en.m.wikipedia.org/wiki/Double_pendulum
  - eru 5y ago
    Yes, Chaos arises in Newtonian systems just fine. They are non-linear. But Quantum Mechanics is linear. See eg https://physics.stackexchange.com/questions/33344/is-the-universe-linear-if-so-why https://physics.stackexchange.com/questions/33344/is-the-uni... for a discussion, and https://www.scottaaronson.com/papers/island.pdf https://www.scottaaronson.com/papers/island.pdf for a longer treatment.
    - goldenkey 5y ago
      QM being linear doesn't make the universe linear. Schrodinger's equation doesn't work across measurements (or universes.) And if you try to weasel out of that by saying we will describe the multiverse instead, you have just created the unexplainable phenomena of being in a specific universe, with no way to accurately describe the process behind the random choice of the universe you reside in.
      - eru 5y ago
        Measurements (and 'universes') are part of interpretations of QM. Not sure they are properly part of QM. I see what you mean though. I'm not sure whether eg the Born rule is enough by itself to explain how (non-linear) chaos arises from linear QM.
meroes 5y ago
> that's what consciousness is How do you go from computation to feeling a toothache? It's like telling me a cucumber is really a Porsche (but worse).
- vokep 5y ago
  Who says neural networks aren't in pain when their fitness (reward function) is subtracted from? or happy or orgasmic when the function is bumped up? Pain/pleasure seem to have easy enough analogue to at least something like a reward function, but what really gets me is colors. I feel like if honestly considered, the word "color" is all that's necessary to disprove materialism. Color is. How? Dunno.
  - PeterisP 5y ago
    Perceptions and feelings are real as you both experience them and could measure their signals in the brain, if you would have the proper tech to do that. And filtered, processed perceptions exist as well. In a "pipeline" in some brain - no matter if biological or artificial - somewhere in the middle you have processed signals of sensor input that have a complex meaning that has only some relation to the actual physical world "seen" by the sensors. Things like color and motion seem one of those; for an intuitive understanding it seems very close to the distill.pub analyses of what some specific middle-neurons in a convnet see.
    - deleted 5y ago
      [deleted]

mjburgess 5y ago

the issue isn't brains no algorithm running on a cpu can move a muscle -- it is precisely that movement is a spatiotemporal property which means no turing machine can realise it movement isn't a symbolic operation

tsimionescu 5y ago
This is such a strange claim to make, I can't even tell what you could have meant. We are surrounded by simplistic mechanical computations moving muscles , and have been for more than a hundred years, since the industrial revolution at least.
gnramires 5y ago
What do you suppose those computers are doing, then? ;) https://www.youtube.com/watch?v=tF4DML7FIWk https://www.youtube.com/watch?v=tF4DML7FIWk https://www.youtube.com/watch?v=tfb6aEUMC04&t=115s https://www.youtube.com/watch?v=tfb6aEUMC04&t=115s
- PeterisP 5y ago
  I would go a step further and look at the research on medical devices for spinal-damage patients which try to literally control their existing muscles through a computer; the concept of neuroprosthesis and https://en.wikipedia.org/wiki/Functional_electrical_stimulation https://en.wikipedia.org/wiki/Functional_electrical_stimulat... working to design algorithms on CPU to move muscles, as the parent post words it.
ineedasername 5y ago
In this very narrow sense that you are defining, no brain can move a muscle either. All it can do is send signals. A computer can do the same. If you are making a broader claim about the limits of hardware vs. wetware the you will need to clarify things a bit further.

eru 5y ago

> It's difficult to even imagine a physical theory with unbounded local information. It seems to open the possibility to crazy things like hypercomputation, which do not seem very well defined. (For example: every 1-1/n seconds, (n>1) from now, flip a switch ON/OFF. At what state will the switch be at t>1s? An at exactly t=1s?) I agree with the latter, but the former? Classical Newtonian mechanics is easy enough to imagine. What baffles me a bit is that quantum mechanics seems to be linear, but we seem to see chaos in the real world. (And exactly that (mathematical) chaos is also what the article exploits.)

istjohn 5y ago
Chaos arises in very simple (Newtonian) systems, e.g. the double pendulum[1]. 1. https://en.m.wikipedia.org/wiki/Double_pendulum https://en.m.wikipedia.org/wiki/Double_pendulum
- eru 5y ago
  Yes, Chaos arises in Newtonian systems just fine. They are non-linear. But Quantum Mechanics is linear. See eg https://physics.stackexchange.com/questions/33344/is-the-universe-linear-if-so-why https://physics.stackexchange.com/questions/33344/is-the-uni... for a discussion, and https://www.scottaaronson.com/papers/island.pdf https://www.scottaaronson.com/papers/island.pdf for a longer treatment.
  - goldenkey 5y ago
    QM being linear doesn't make the universe linear. Schrodinger's equation doesn't work across measurements (or universes.) And if you try to weasel out of that by saying we will describe the multiverse instead, you have just created the unexplainable phenomena of being in a specific universe, with no way to accurately describe the process behind the random choice of the universe you reside in.
    - eru 5y ago
      Measurements (and 'universes') are part of interpretations of QM. Not sure they are properly part of QM. I see what you mean though. I'm not sure whether eg the Born rule is enough by itself to explain how (non-linear) chaos arises from linear QM.

meroes 5y ago

> that's what consciousness is How do you go from computation to feeling a toothache? It's like telling me a cucumber is really a Porsche (but worse).

vokep 5y ago
Who says neural networks aren't in pain when their fitness (reward function) is subtracted from? or happy or orgasmic when the function is bumped up? Pain/pleasure seem to have easy enough analogue to at least something like a reward function, but what really gets me is colors. I feel like if honestly considered, the word "color" is all that's necessary to disprove materialism. Color is. How? Dunno.
- PeterisP 5y ago
  Perceptions and feelings are real as you both experience them and could measure their signals in the brain, if you would have the proper tech to do that. And filtered, processed perceptions exist as well. In a "pipeline" in some brain - no matter if biological or artificial - somewhere in the middle you have processed signals of sensor input that have a complex meaning that has only some relation to the actual physical world "seen" by the sensors. Things like color and motion seem one of those; for an intuitive understanding it seems very close to the distill.pub analyses of what some specific middle-neurons in a convnet see.
  - deleted 5y ago
    [deleted]