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> So, it seems to me a reasonable starting assumption that intelligence is a result of the mechanistic universe. > Do we have any evidence for something outside the physical, mechanistic universe impacting human cognition?

Problem is, even granted the above, that's not enough of an argument that AGI is only a matter of mechanism.

Take the analogy with pain. We've discovered the mechanism for pain. That it's e.g. some stimulus applied to skin which sets of nerve signals that register in the brain. To then say that the experience of pain is the same as the physical mechanism we've discovered still misses a key step:

what does the experience of pain inhere to, and is that the same subject as that for the mechanism of pain?

Comparing AGI and human intelligence has the same problem. We don't know exactly what is intelligent in either case, let alone whether the two are comparable. So it's not a question of intelligence per se, but of that which is intelligent. Maybe AGI, the way we are thinking and talking about it, is unavoidably tangled with having to grapple with [self-]consciousness.

Do you think the self-consciousness that we possess is the result of physical processes going on in our brain and body, or do you think something outside of physics is required?

If I made a careful atom by atom (or quark/lepton/boson) copy of every atom in your brain and body in a different location, would that new copy be intelligent?

If our intelligence is purely a result of physical processes, then why do you suppose it would be impossible for us (or more advanced future beings), to construct a machine which can also follow those processes?

If you think your intelligence is not reducible to purely physical processes, then… what is this meta-physical thing that is required for intelligence? Does it interact with anything other than intelligence, or is it only involved with intelligence? Is there any reason or evidence we should assume this meta-physical intelligence?

> ..., or do you think something outside of physics is required?

I am most sympathetic to the argument that self-consciousness is an emergent phenomenon that is not easily modeled, but is nevertheless derived from physics. In the context of my previous comment, it is this emergent phenomenon that is deemed "intelligent".

> If I made a careful atom by atom (or quark/lepton/boson) copy of every atom in your brain and body in a different location, would that new copy be intelligent?

Yes.

> If our intelligence is purely a result of physical processes, then why do you suppose it would be impossible for us (or more advanced future beings), to construct a machine which can also follow those processes?

I think it is possible, and not too far off to boot. We might get (maybe we already have gotten) the intelligence without the particular emergent phenomenon of self-consciousness that is of the kind humans possess, at least not at first. Some of us will call that AGI, some of us won't. Because we are still working out the terminology and taxonomy. Discussions like these in HN help.

Maybe we'll get the emergent phenomenon soon thereafter. If it is in fact intractable to model (and therefore to train for directly), it may happen unpredictably. Exciting times.

I think a mechanistic universe is not necessarily a computation, so purely physical intelligence is also not necessarily a computation. But I'm not prepared at the moment to go dig up the alternatives to "computation" and "metaphysical process", or to figure out how a deterministic (or even stochastic) process could be uncomputable.

> so purely physical intelligence is also not necessarily a computation.

We're going to get into semantics pretty quickly, but I would argue that at least purely physical intelligence is a procedure that is capable of being run on a machine that exists in our universe.

I would also argue that, such a machine is _at least_ turing complete (since I would think a general intelligence should be capable of emulating a turing machine in the same way that humans are able to do so). I would happily accept that it's possible that being turing complete is a necessary, *but not sufficient* condition for intelligence. That is, I could see a world where intelligence requires some form of hyper-turing machine, that is able to solve some non-turing computable problems.

However, I would argue that even if intelligence does require non-turing computable functions, there exists *a* machine which can perform those procedures (that is, we exist). Thus, in this hypothetical universe where intelligence is non-turing computable, we would then have an existence proof for a hyper-turing machine which can compute non-turing computable results. In this universe, then, I'd argue that anything that can be produced by this "hyper-turing machine", _is_ "physically computable", even if not "turing-computable".

Ultimately, if we accept the premise of a mechanistic universe, I think humans are an existence proof of a machine capable of producing intelligence. Then, I think it follows that it *cannot* be physically impossible to create a machine capable of producing intelligence. Whether we call that machine a "computer", though, I don't have a strong preference.

Neither humans nor any physical device is Turing complete; only bounded computations can we perform. What do you mean by mechanistic? Mathematical? Deterministic? Non-dual with no unmeasurable causes?

> What do you mean by mechanistic?

So, I’ve only used it in a “I understand what it means and what I mean by it” manner in the past, and I haven’t rigorously defined it for myself.

I’ll do the best giving an off-the-cuff definition, but I’m sure it will have some holes and would be improved with some time spent thinking about it, or reading to crib a definition from someone else who has already put in that time.

I think my definition of a mechanistic universe would be:

A universe that transitions from one state to an adjacent state through a consistent set of rules.

From your options:

- mathematical? I’m think yes, but potentially only if “mathetics” is defined broadly.

- Deterministic? I don’t think this is a requirement for a mechanistic universe. My bet would be on a deterministic universe (through an Everettian interpretation lens), but I think something can be mechanistic while being stochastic, so long as the rules determine the probabilities. That is, I would consider a computer with a true source of randomness to still be mechanistic.

> Non-dual with no unmeasurable causes?

Non-dual, yes. That is the primary meaning for me. “With no unmeasurable causes” is a phrasing that makes me slightly uneasy. I could imagine a situation where, if the universe is stochastic you could end up in a situation where you cannot precisely identify the specific cause for a specific event. But, I think as the spirit of this question is intended, yes.

Thanks, that all makes sense. Do you follow Sean Carroll's takes on many worlds? A very consistent philosophy of reality, and some interesting math starting to come out with space-time itself being an emergent feature of Hilbert space evolution of the wave equation (where it is constructed essentially out of varying degrees of coupling between different states). Even a paper where this sort of coupling-derived space might obey the Einstein equations.

I listen to his podcast, and I’m definitely partial to the many worlds interpretation, so I end up taking in a lot of his explanations of it.

The work he’s doing in that area is super interesting, and sounds promising (of course, I’m getting primarily Carroll’s take on it when I hear about it, so it makes sense that it sounds promising!), but the math itself is above my head.

I am super interested to see if it ends up moving the ball forward on resolving the GR/QM conflicts.

I personally don't think it will but I guess it could, it's as good a model to start from as any. That's kind of the problem though, it's not actually better than the modern version of the Copenhagen interpretation unless you think wave function collapse is a physical event that's caused by (something in) your brain. If you think that, Copenhagen's obviously not correct, as your brain can't cause anything that it itself wasn't caused to do, because free will does not exist. If you think of wave function collapse as not a physical event and not caused by anything (except by the physics of the universe following the original state of the universe, if you don't like the idea of a block universe in configuration space), it's totally fine and is equivalent to Multiple Worlds. Don't think of the Multiple Worlds as things that physically exist either though.

Can we stop with this stuff? It is a 100% useless distinction, Turing machines can only ever use a fixed amount of memory, so we can run any Turing machine for as long as we want to, we can just pause it, “change the tape” to a bigger one, and continue.

Well, it's not useless mathematically. The Turing machine cannot run on all inputs with a bounded tape size. The quickly growing functions show pretty strongly that no physically incarnateable device can compute easy to specify functions on inputs less than 1000. "Turing machine" or Turing equivalence are pretty precisely defined mathematical concepts, so using them in different senses is a bit perverse; in my mind, more perverse than using literally to mean figuratively. Also, how does one change the tape in ones brain? I'd love a pensieve but those also are not physical, at least not yet.

The thing I'd really like is a Turing machine where the nth transition took 1/2^n seconds, so we could run them to infinity in just two seconds.