[celeritascelery]

The reductionist argument seems to be “the brain is just a meat computer and is conscious, therefore a complex enough silicon computer will be conscious as well”.

I find this very similar to alchemy in the 15th century. The idea was “gold is heavy, malleable, lustery metal, and so is lead. We have observed substances can be converted others. Therefore with the right chemical process we can convert lead to gold”. The implicit assumption is that since the two things are similar, they can be made to exhibit the same properties with the right science. I.e. lead can become gold.

This is the same as the “meat brain/silicon brain” line of reasoning. But as we learned with more advanced chemistry, lead cannot be turned into gold (at least not in the chemical way they were expecting).

So the burden of proof does lie with those making the assertion that: “meat computer has consciousness”, therefore “silicon computer could have consciousness”. Lots of people assume this is just a given without any evidence. Just as alchemists assumed from the similarities between gold and lead meant they could be chemically converted. I would postulate chemistry is much simpler then consciousness.

[simonh]

It depends on whether consciousness is a computational process. If it is then meat or metal really doesn’t matter. We know this because mathematicians have proved that any sufficiently capable computer can perform any computation.

So the lead to gold analogy doesn’t hold. It would be as if scientists had proved that any element can be transformed into any other element. Well, if that was true, then yes it follows that lead could be turned into gold, in a universe where that had been proved.

So is consciousness actually a computation? Of course that’s a matter of opinion. All I’m saying is, I think so yes, I think I have coherent reasons for believing so, and none of the counter arguments persuade me otherwise so far. I can’t prove it to you though, we’re just talking.

What I can say is, this or that argument seems to me to have this or that flaw, or lead to this or that consequence or conclusion that I find unlikely or absurd. Dualism is such a conclusion I find absurd, and I think most of the actual arguments against computational consciousness seem to at least reduce to attempted refutations of materialism, or out and out dualism.

[celeritascelery]

> It depends on whether consciousness is a computational process.

Absolutely agree. But that is the assumption that I would liken to alchemists comparing lead and gold. We know almost nothing about the brain. We know almost nothing about consciousness. But yet some people assume that consciousness is computable just because we don't know anything else it could be (just as alchemists assumed gold and lead could be transform because they were both chrysopoeic base metals. They hadn't discovered atomic theory yet). When all you have is a hammer, everything starts to look like a nail.

We know that the vast majority of numbers are uncomputable[1]. We also have proved that computation is incomplete[2] and can be undecidable[3]. It seems perfectly logical that consciousness is not computable. Or it could be computable, I obviously don't know. If someone makes the claim that consciousness is computable, then the burden of lies with them. We can't accept that on blind faith. At this point it is all opinion and speculation (as you said) because we still can't even define consciousness in a rigorous way. (and I don't think we will ever create artificial consciousness until we can define it, but that is an orthogonal issue).

[1] https://en.wikipedia.org/wiki/Computability_theory [2] https://en.wikipedia.org/wiki/G%C3%B6del%27s_incompleteness_... [3] https://en.wikipedia.org/wiki/Undecidable_problem

[simonh]

I’m not assuming anything or accepting anything on blind faith, and I don’t think I’ve given you any reason to think that I am.

If anyone says that they think it is either this or that, it’s reasonable to ask them to justify that belief. There’s no reason to resort to using language like assume, blind faith, etc.

[kazinator]

That's not necessarily a reductionist argument if it respects that the consciousness has a drama of its own that is not related to the low-level parts of the substrate; i.e. that the consciousness is irreducible. The mere hypothesis that something can be ported to silicon doesn't reduce it; it respects the complexity of the abstraction itself.

Also, "the meat computer has consciousness" independently requires proof. Every meat computer thinks it has consciousness, and we just take their word for it, based on our own experience as a meat computer.

If the thing making the same claim is not a meat computer, then we don't believe it in the same way: "I know meat computers are conscious because I am one; you say you are conscious but you are not a meat computer, therefore I don't believe you".

In the same way, we could deny that an extraterrestrial life form is conscious, if it's not made of anything resembling meat.