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Comment by ramraj07 | Hacker News Reader

Wait isn’t any Turing complete programming language sufficient to eventually reach general AI

You're assuming that intelligence is a computational process, but the sum total of what we know about intelligence says it probably isn't.

(Unless you're making a more general reductionist statement that everything in the universe is a computational process - that kind of reductionism is understandable coming from people who work with computers for their job - but this is then a philosophical stance, not scientific, and frankly a very strange one.)

> but the sum total of what we know about intelligence says it probably isn't

Source? I am not aware of any other known process in the universe that could not be simulated by a Turing machine.

Assuming that the universe can be simulated by a Turing machine is a strong and weird claim that needs to be defended, not the other way around.

We know that Turing machines are very limited things and that the computational processes they carry out also very limited in applicability.

What's the evidence that the universe is more limited that a Turing machine?

Just the fact that we can imagine things that can't be computed by a Turing machine should clue you in that it's probably otherwise.

> We know that Turing machines are very limited things and that the computational processes they carry out also very limited in applicability.

Again, source? Do you know of anything that is able to perform a computation that a Turing machine cannot?

> Just the fact that we can imagine things that can't be computed by a Turing machine should clue you in that it's probably otherwise.

Like what? Uncomputable numbers like Chaitin's constant? We can "imagine" them by stating their definition, but we cannot compute them. Or do you have something else specific in mind?

>Like what?

The halting problem is (I think?) the standard example.

Here's a short video on it https://youtu.be/macM_MtS_w4

Chaitin's constant is closely tied to the halting problem: Each bit essentially tells you if a program (in the particular order the programs are listed in the constant) halts or not. Computing every bit in there would mean knowing for every program if it halts or not, which would solve the halting problem, which we can prove is impossible. So we cannot compute that constant.

> Do you know of anything that is able to perform a computation that a Turing machine cannot?

That's a circular argument, because "computation" is literally defined as "something that can be computed by a Turing machine".

That said, the first month of the first year of a CS education is "here's these problems that can't be solved by a Turing machine, mind=blown". (At least where I studied CS, that is.)

A Turing machine needs a discrete clock cycle, if intelligence requires quantum mechanics that has entanglement through time, that would be one example.

I’m not making the statement that everything in the universe is a computational process, only that everything in my brain is, at least the functionality of my brain towards creating my consciousness.

Now can I prove that ? Of course not. But it seems like a fairly solid working hypothesis (any other alternative hypothesis sounds far more quacky anyway? What quantum entanglement of mocrotubules?).

Like the notion that all of natural language can be modeled fully if you just use enough finite state machines — surely true; just a wee bit inefficient.

If you had a custom chip it could be efficient. Determining which state machines would still be hard.

Wait no, that can't be true. Finite state machines are only as powerful as regular expressions; you need pushdown automata even for programming languages, surely you can't model natural language with finite state machines? (maybe an infinite number of them, but I'm doubtful even on that - I'd have to review the theory to be sure though)

It is true; keep in mind that real computers are strictly speaking FSMs, not Turing machines, due to having a finite "tape". It's just vastly more useful to think of them as such when programming.

In practice, both people and machines can only handle a finite amount of nesting, so you could do it though it would be awkward to express.

Perhaps the fact that some words can never follow other words would make it tractable.

Technically that is a conjecture known as the Church-Turing thesis, which states that any computable function can be computed by a Turing machine. Here "computable function" uses the informal definition 'any function that a human can compute', not the formal definition of the recursive functions (which are proven to be solvable by a Turing machine).

Yeah, I would even say a large amount of NAND gates should do it.

Maybe, but that is not helpful in the sense that it doesn't guide research in how to get there.

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