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A Brief Explanation of Greg Egan’s Dust Theory

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Re: A Brief Explanation of Greg Egan’s Dust Theory

#21

Post by codethief »

db48x wrote: post #13
codethief wrote: post #7

He lost me right in the second paragraph: > Because computation is sort of subjective, just a set of relations that can be usefully interpreted as representing a function, this seems to imply that the function you identify with can be interpreted as being simulated by any sufficiently complex set of relations. Can anyone explain? I'm already struggling with the premise: Why should computation be subjective in the fir…

He states it in the previous sentence: > If you think experience is simulatable, [and] you buy computational or “patternist” theories of identity… Basically, the inner experience of any sapient computation (aka "person") is subjective.

I would counter that by saying that:

1) this has nothing to do with computation.

2) my subjective experience is objectively there. No one questions what I am thinking. (That is, no one else looks inside my brain and claims: This is not what your thinking!) My thoughts might be my own personal view and differ from other people's thoughts but their existence is not up for debate.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#22

Post by croissants »

tomrod wrote: post #2

Interesting article! As linked in the article, Egan posted some FAQ/counterarguments for issues raised here: https://www.gregegan.net/PERMUTATION/FAQ/FAQ.html

Nice, IMO this (short) FAQ has a lot more useful info than the featured article. His claim at the end that creating intelligent life through evolution is deeply immoral confuses me, though -- by all accounts, we arose through that process, and relatively few people seem bothered by it.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#23

Post by xwdv »

I think I can somewhat grasp what is being explained but maybe not really.

As a thought experiment, if you had a screen of fixed resolution that displayed random color pixels, given an infinite amount of time, you could watch an entire specific movie (along with every other image), perhaps in random order, but from the movie's perspective if it were conscious it would not be aware of whatever order it's playing in, it would just perceive itself to be going forward I guess. The movie itself is like a function that displays an image as a function of time.

So I guess they're saying consciousness in Dust Theory could be like that? What we perceive as a conscious moment is a brief output of random noise for a random timestamp?

Re: A Brief Explanation of Greg Egan’s Dust Theory

#24

Post by croissants »

GeekyBear wrote: post #8
domenicd wrote: post #3

A while ago I wrote up my own take, inspired largely by Permutation City but also by Tegmark's mathematical universe hypothesis: https://blog.domenic.me/mathematical-consciousness/ To me this line of thinking is very attractive. As someone who has been a mathematical Platonist forever, this gives a very satisfying answer to big questions like "why is there something instead of nothing" and "why is our universe so per…

> Permutation City I haven't read that book since the early 90's but it dealt with ideas that have really stuck in my mind.

The main detail I remember from that book is that credit card companies would track whoever you dined with at a restaurant and then serve you ads featuring computer-generated people who resembled those people to manipulate you into trust. Pretty ahead of its time for 1994!

Re: A Brief Explanation of Greg Egan’s Dust Theory

#26

Post by ardy42 »

MiroF wrote: post #18

> This is sort of like the Boltzmann brain idea but even worse because it applies to any set of relations. According to Egan’s argument all possible experiences that can be computed by any sufficiently complex set of relations are in fact computed by them. This idea seems identical to the Boltzmann brain hypothesis and I don't understand how this paragraph differentiates it at all.

>> This is sort of like the Boltzmann brain idea but even worse because it applies to any set of relations. According to Egan’s argument all possible experiences that can be computed by any sufficiently complex set of relations are in fact computed by them.

> This idea seems identical to the Boltzmann brain hypothesis and I don't understand how this paragraph differentiates it at all.

I don't claim to totally understand this, but my impression is "Dust Theory" implies that the mind is more frequently simulated than in "Boltzmann brain" theory. IIRC, the latter imagines a literally brain being formed briefly out of matter.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#27

Post by db48x »

codethief wrote: post #21
db48x wrote: post #13

Earlier quoted context omitted.

He states it in the previous sentence: > If you think experience is simulatable, [and] you buy computational or “patternist” theories of identity… Basically, the inner experience of any sapient computation (aka "person") is subjective.

I would counter that by saying that: 1) this has nothing to do with computation. 2) my subjective experience is objectively there. No one questions what I am thinking. (That is, no one else looks inside my brain and claims: This is not what your thinking! ) My thoughts might be my own personal view and differ from other people's thoughts but their existence is not up for debate.

This has everything to do with computation, because the mind is just software running on a funny kind of computer. In the novel, many people have had their minds uploaded into regular electrical computers as well, though they're generally not able to run in real time.

That's not a counter, because it's just what I said. We all have a subjective inner experience. The premise of the novel is that this subjective inner experience is both necessary and sufficient for immortality. The story is an exploration of solipsism, though most of the characters in it choose to take people with them rather than to exist in immortal isolation.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#28

Post by croissants »

aaron-santos wrote: post #20

The article really ought to close the loop by tying it back to the final 10% of the book. The big point in the book is that you can craft arbitrary surjections and have an infinite set of justifications for your subjective experience. A physical substrate is just as good as a computational/mathematical substrate. In this sense you can bootstrap your simulated existence into the immortal world of forms.

The part I don't understand about this, which is the same as the part I don't understand about dust theory, is that it seems to ignore the distinction between an abstract representation of an object and the object itself.

By the logic of dust theory, I can walk into a bank and say "give me the money, or else I'll throw this handful of sand into the air, and it might encode a universe where you're tortured for a billion years!"

Re: A Brief Explanation of Greg Egan’s Dust Theory

#29

Post by xwdv »

boxed wrote: post #15
j-pb wrote: post #5

I don't know the original theory, but this explanation is brief to the point where it's nonsensical.

Might be because the entire thing is nonsense. Entropy shoots a hole in the entire thing as far as I can tell. The problem is that the information can never be retrieved, so if it exists or not is really pointless.

If you are the information though then you have retrieved it.

Re: A Brief Explanation of Greg Egan’s Dust Theory

#30

Post by Udik »

codethief wrote: post #7

He lost me right in the second paragraph: > Because computation is sort of subjective, just a set of relations that can be usefully interpreted as representing a function, this seems to imply that the function you identify with can be interpreted as being simulated by any sufficiently complex set of relations. Can anyone explain? I'm already struggling with the premise: Why should computation be subjective in the fir…

Just by chance, I happened to try to explain the dust theory to a completely uninterested subject today over lunch :)

I tried to make it as brief as possible like this: some people believe mathematical truths are necessary and therefore that they exist independently of us discovering them. For example, the entire set of theorems that can be proven from a given set of axioms is already there in the axioms themselves- our calculations are a process of discovery, not of creation. Or to make another example, all the decimal digits of PI "exist", independently of us running the calculations that make them knowable to us.

But suppose we had a function that produces the succession of discrete states of a self-conscious mind (for example, a detailed description of the state of each neuron at any given microsecond). How does the act of actually calculating the values of the function- discovering them- affect the self-perception of that mind? Does it really care if someone is running the calculation?

There is a fun anecdote in Permutation City: the story of an old misanthrope who, nearing death, orders the creation of a digital copy of himself immersed in a simulated world; however, having no desire to communicate with the outside world, he asks for the simulation not to have any inputs or outputs. The algorithm is built, but once it's passed through an automated code optimizer, the optimizer spits out nothing: because a calculation that makes its results known to no-one is empty!

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