[csee]

  "To achieve a persistent mapping for a significant time you'd probably need an iron bar something like size of the observable universe"

But the observable universe exists. So why can't the observable universe appropriately substitute for the iron bar in his argument?

  "As for doubting the field of rocks can be conscious"

Just to be clear, you don't doubt that a sufficiently large field of rocks is conscious as long as it is performing the same computation as a brain?

[simonh]

On the first issue, that's the Boltzmann's Brain proposition, and well, yes. Given infinite monkeys, you'll get Shakespear. I don't see what that has to do with whether consciousness is computational or not. It certainly doesn't refute it.

>Just to be clear, you don't doubt that a sufficiently large field of rocks is conscious as long as it is performing the same computation as a brain?

No I don't, for the same reason that if you slowed down my metabolism by a trillion times, I would still be conscious. I wouldn't seem conscious to you, but that's a problem with your perception, not with my nature. I'd just be conscious very slowly. It wouldn't fundamentally change the nature of who or what I am. For rocks interacting according to rules, substitute atoms. Is a rock any more or less inanimate than an atom? This is all just materialism 101.

[criddell]

> Given infinite monkeys, you'll get Shakespear.

That seems like an odd assertion. Just because you can produce and infinite number of something it doesn't mean that every variation will be produced. I can generate an infinite list of numbers that doesn't contain '3'.

[undersuit]

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

>I can generate an infinite list of numbers that doesn't contain '3'.

But you can't generate an infinite random list of numbers that doesn't contain '3'. The complete works of Shakespeare are just another one of the infinite permutations of characters a monkey could type.

[csee]

What about the arguments outlined in the article? You first dismissed the arguments because an iron bar couldn't have enough physical states. But we both accept that there are physical objects which do have enough physical states, even if we have to use the entire observable universe as the object that the mapping draws from (and that's not related to the Boltzmann Brain). So the arguments in the article seems to be either ignored or misunderstood.

Also, materialism =!= substrate independence and invariance to speed of computation. Consciousness can have a materialist explanation yet also be substrate dependent to an extent.

[simonh]

I actually don't think the observable universe is big enough, and that's been demonstrated mathematically by better people than I, but the universe as a whole including non-observable parts might be big enough.

I don't see how this is not the Bolzmann's Brain proposition. What's the difference?

>Consciousness can have a materialist explanation yet also be substrate dependent to an extent.

I suppose so, maybe there's a quantum mechanical component, but even in that case why couldn't that be built into a computer? What sort of substrate might it be that we couldn't build it into a robot for example?

[csee]

If the observable universe is too small, what about the observable universe sampled at multiple points in time? Or just an iron bar that's repeatedly sampled along a time interval, with the desired encoding changing between each sample such that the object doesn't need to undergo much change it state in order to map to distinct things. Each sample increases the number of physical states that we can create a mapping from. If we still don't have enough states, we can draw more samples over more points in time to create a longer string of bits for the mapping.

Or another way to do it would be to repeatedly sample the same object at the same point in time, and simply change the desired encoding on each sampling, e.g. on a first pass we use F_0(x), on a second pass we use F_1(x), and we concatenate the output of F_0(x) and F_1(x) into a single large bit array.

The Boltzmann Brain says that our conscious experience at the current moment is a chance quantum event. It might not even involve the whole universe, it could be a local quantum phenomenon. That seems distinct to the argument in the article, which is that physical states (quantum or otherwise) can be mapped to an arbitrary string of bits with the encoding chosen by the person doing the mapping, and the output of this mapping (which is itself a string of bits) can correspond to a computation on a Turing machine, therefore inanimate objects with sufficiently large numbers of physical states could be said to be running a proposed consciousness.exe, which leads us to an absurd/extreme form of panpsychism.

[simonh]

>The Boltzmann Brain says that our conscious experience at the current moment is a chance quantum event.

I just meant that the proposition that an iron bar might be viewed as containing a consciousness, is similar to the idea in the BB proposition that consciousnesses might arise spontaneously in random matter in space. Well they might, but that doesn't prove or refute anything about consciousness.

The bit about Boltzmann's Brains possibly outnumbering real evolved brains is a separate philosophical question I didn't mean to address, and I apologise for the confusion.