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Comment by sega_sai | Hacker News Reader

I posted the article because it is thought provoking, although I disagree with it. The reason is for example statements like this "The real problem is that computers are not in the world, because they are not embodied." "And I shall argue that they cannot pass the full Turing test because they are not in the world, and, therefore, they have no understanding." First I think that whether something is embodied or not doesn't matter. Our senses in the end could be likely approximated by arrays of numbers fed to a computer, so I don't think lack of body is such an issue. Regarding understanding by machines, that is clearly the issue for current AI, but at least based on what I know about modern machine translation, there is already something that works with concepts/abstract terms and their relations, which looks to me like a beginning for abstract reasoning...

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As others have said, I think this is a better argument against machines emulating humanness than it is against the broader category of "general intelligence".

For me it always comes down to: If we assume the human mind to be a physical, deterministic phenomenon, then an informational, deterministic system could simulate it. It's as simple as that. To take the brute-force route, every atom in a human body could be simulated, which would include its intelligence.

Now, that says nothing about time-scale or practicality. It doesn't even say anything about whether electronic computers as we know them can achieve the physical density necessary to simulate something so complex, given the natural resources we have available. But in principle, unless you believe in the metaphysical, there's no denying that AGI is something that can exist.

Why do we need the assume a deterministic system? As long as it physical and we believe physics can be described with computation, we can simulate it. Some randomness doesn't matter.

Thanks for posting, I also disagree with it. I think using this authors high level stance is that only the human physical experience can lead to general intelligence. By this logic a blind person or quadrapeligic might not be generally intelligent.

Not quite. The unconscious management of the internal systems that keep us alive are as much a part of that physical experience, as our motor-sensory apparatus. In fact, some neurologists suggest that these unconscious urges are the most likely governors of 'conscious' action. That's a gross oversimplification... Dr Antonio Domasio explores the idea in fine detail in his books. Particularly 'The Self Comes to Mind'.

Absolutely not. People with disabilities still experience the world. See Helen Keller. Your reasoning would only apply to people with no sense and no way to communicate at all.

I'd recommend Daniel Dennett's talk If Brains are Computers, Who Designs the Software? as a counterpoint to this article [1]. Dennett's talk is a bit long but I mostly enjoyed it, especially when he points out the computerphobia of many of his colleagues.

Of course, it's easier for me to agree with Dennett than for many other people, because I'm a computationalist in the philosophy of mind and suspect that consciousness is an emergent property of certain computations. It might in theory even be possible to realize that by analytical insight - though probably not in practice. I'm generally not a fan of the philosophy of mind, though, because it mostly consists of speculation and intuition pumping.

[1] https://www.youtube.com/watch?v=TTFoJQSd48c

> I'm a computationalist in the philosophy of mind and suspect that consciousness is an emergent property of certain computations.

I'm not a philosopher of any variety and this always seemed like a much more plausible scenario to me than some kind of consciousness magic sauce. It is pretty amazing to watch the intellectual contortions people will twist themselves into to avoid reaching this conclusion. Like deep down they are certain their lived experience can't possibly be an effect of purely physical processes, but they need to couch that belief in sufficiently convoluted words that they can convince themselves they aren't just talking about souls.

It doesn't seem to be required that an animal have sensory information. [1] I'm not convinced by the argument that a computer can't think just because it doesn't experience the world. If anything, experiments like (1) show that we may be able to better understand how brains work if we get rid of all the "noise" from external stimulation so we can better understand the signals.

[1] https://www.quantamagazine.org/random-search-wired-into-anim...

My hunch agrees with the paper. Because computers operate on the rational numbers instead of the real numbers, they can never be embodied. They are always in a simulation...

Maybe I don’t understand your point, but our senses are also compressed to some extent. Your synapses fire or don’t fire, providing digitized input for some of your senses like hearing. At any point there is a discrete amount of hormones in your body. etc etc. That doesn’t seem categorically different from any man made sensor.

Our sensorium could be indistinguishable from how it'd be in a simulation without impacting my point. Software can hop from host to host (all Turing machines can simulate each other) but living intelligence is embodied.

Because of this, no matter how "smart" computers get, we can't trust them not to do stupid stuff. They are smart like that kid in high school who comes up with a formula to turn the world into silly putty, and is stupid enough to use it. There is more than one kind of intelligence, here the argument is that some kinds of intelligence require having skin in the game.

But would it be impossible to have artificial “skin in the game”? Is there no robot body that could serve this purpose?

Why isn’t computer hardware already as “embodied” in the physical world as our brain matter is?

We can't trust people not to do stupid stuff.

> They are smart like that kid in high school who comes up with a formula to turn the world into silly putty, and is stupid enough to use it.

So that kid isn't intelligent?

This is like saying CD players will never be as good as vinyl record players because the first use digital signals (rational numbers) and the second analogue (real numbers).

if you want to be pedantic record players are also digital because they can't represent anything tighter than an atom or the molecule of vinyl

Isn't everything digital to a point, since we can't ever measure anything smaller than the Planck length?

I'm on record saying heterodox things about the Nyquist theorem and SACD 1-bit DAC, so you are on topic. :)

In that case, since we are here and it's Friday and everyone needs to take it easy from time to time, here's my proof that we don't live in a simulation: according to [1], ray tracing is computationally undecidable. For example, say you are in a museum at night, and a light bulb turns on in a room on the third floor, is it still dark in some room on the first floor? This problem is undecidable using the axioms of geometric optics.

Of course, geometric optics is like real numbers, and the actual world is discrete: light is a finite collection of photons. So, you can do the simulation by simply emitting a number of photons from each light source and tracing them all the way until they are all absorbed. We can still live in a simulation, but one without algorithmic shortcuts, a simulation where you simulate every single photon.

Now, I'm sure you can come up with your own version of proof that we can't live in a simulation using Nyquist's theorem. If you do, and your Friday is not too busy, please share.

[1] https://users.cs.duke.edu/~reif/paper/tygar/raytracing.pdf

My audiophile friends would vehemently agree with this statement :)

Call us when they can back up this assertion in double blinded tests.

They can rather easily discern between the two in double blind tests. The vinyl recording has a noticeable amount of noise in it. Vinyl record players can't exceed the kinds of signal to noise ratios that human hearing can detect. The more ridiculous claims are the audiophiles who pretend to distinguish between ultra high sample rate audio and 44100Hz or 48000Hz sampled audio.

You are comparing the wrong things in the test. Play the vinyl record, recording it in cd quality, then compare that recording with the original vinyl. They won’t be able to tell the difference.

Yes, the analogy extends more than initially apparent :)

People who vehemently agree that vinyl is better than digital audio are a big part of the reason "audiophile" is basically derogatory nowadays. Reasons being:

- Vinyl gets dust and scratches that degrade signal.

- Dragging a needle along a surface is an inconsistent and limited mechanism for signal transfer.

- Vinyls are always derived from digital files these days anyway! Except for pre-digital prints, studio rate digital is as "pure" as it gets.

P.S. Tube amps are not better than chip amps either, it's a complete myth. Every measurement a tube amp does well at is beatable with a cheaper chip amp design. People think we can do 10 gigabit Ethernet and 4g LTE radio bandwidth with chips, but not accurately control a speaker producing audible frequencies? Please.

Audiophile products have a weird way of capturing people's hearts despite having no merit. I think it's partly because people hear their favorite music through a device and misplace their feelings for the music onto the device, and partly because they are biased towards rationalizing purchases even when they've been conned by some pseudoscience or empty marketing.

> Because computers operate on the rational numbers instead of the real numbers,

Computers are just devices that perform computations. It's perfectly possible to construct computers that operate on values that are continuous and not discrete. In fact, such computers have been constructed before. They are know as analog computers and were used for things like numerically solving differential equations.

This is not even true. We have symbolic processing that can manipulate and formulate with non-rational expressions. This article is so worthless.

You don't need analog computation. The theory of Computable Real Analysis still assumes a digital computer: https://en.wikipedia.org/wiki/Computable_analysis

See here for a concrete application of the theory: https://icfp19.sigplan.org/details/icfp-2019-papers/15/Sound...

Another application is the Android calculator, which computes over exact real numbers in the sense described by Computable Analysis.

Finally, it's debatable whether analog computation achieves true computation over the real numbers. The presence of physical noise, and the fact that many physical quantities (like electrical charge) are ultimately discrete at the quantum level, implies that it doesn't really work AFAICT.

It seems likely that absolutely nothing is analog. The best theories about physics are all quantized. The only things that we don't have strong quantum theories about are things we barely understand, like time and gravity. And that's just because we haven't found the quanta yet.

It has been a minute since I picked up my information theory book.

However if I remember correctly continuous signals (that is functions of the reals) can be represented without loss with a finite (but sufficient number of) discrete samples.

As long as all those reals are computable ;) https://en.m.wikipedia.org/wiki/Computable_number

It's fully possible for a computer to do symbolic math without reducing the symbols to a decimal.

Of course! I meant my comment to be tongue in cheek, but saying that some numbers are uncomputable is not incompatible with symbolic math on a computer. Note that for example Pi is computable, despite having an infinite decimal expansion.

> Because computers operate on the rational numbers instead of the real numbers, they can never be embodied. They are always in a simulation...

I read the exact opposite argument yesterday but not from an AGI perspective: https://getpocket.com/explore/item/a-new-theory-explains-how...

The counter-point to this: Brains.

Brains are computational devices that are embodied.

Camera pixels are pretty real to me

Actually, digital computers can compute over the real numbers. They can compute quite a lot over the real numbers, even. See https://en.wikipedia.org/wiki/Computable_analysis#Basic_resu...

This even has some concrete applications. See this: https://icfp19.sigplan.org/details/icfp-2019-papers/15/Sound...

Finally, saying that digital computers can't compute functions of the form Real -> Real is like saying that a computer can't compute functions of the form (Int -> Int) -> (Int -> Int). In other words, it's like saying that higher order functions are impossible.

This actually makes sense to me, but for those who aren't familiar with set theory, you may want to link this for context:

https://en.wikipedia.org/wiki/Continuum_hypothesis

"Real numbers" have some problems. Information density, for one. Imagine a real number, say 0.27777..., represented as a point on a piece of string, with zero being one end and 1.0 being the other. That point represents infinite information density. It also would seem to run afoul of some of quantum mechanics.

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