Lee Corbin writes:
> So if I understand you right, this is where the difference between
> a book and a person arises. When a book's letters are scattered over
> the cosmos, the information is lost, but when the observer moments
> are so scattered, the subjective experience still remains.
> Now we suppose from quantum mechanics that the Bekenstein bound
> on the number of states a human can be in is less than 10^10^45.
> (Tipler, 1993, "The Physics of Immortality".) So each state of
> your life is a very special small subset of all those states.
> Let's do something special with just *one* life that you've
> led (will lead) in the universe, one life, that is, in a particular
> I propose to take something quite a bit like observer-moments and
> ask some questions about it. Suppose that an exact frozen replica
> of your brain is made corresponding to each 10^-42 seconds of your
> life. This gives us about 10^42 * 10^7 * 70years, or about 10^50
> states (a far cry from all those possible for humans, 10^10^45).
> We place those 10^50 states in a long row, and then, for an audience,
> we round up all the billions of observers in the visible universe
> to watch the show. First the spotlight is on your brain the second
> after you were born. Then one 10^-42 seconds later the spotlight
> moves to the next frozen brain, and so forth.
> The audience is placed in the same frame of reference as the moving
> light, and so they see an apparently continuous evolution of your
> How is this any different from what happened to you actually? From
> an external scientific point of view, it seems remarkably identical.
> (I am ultimately to claim that something essential---but not
> "consciousness" or anything like that is missing, but rather
> *causality* is missing.)
Well, it depends on what you believe about how brains work. Let's go to the other extreme and make the observer moments very long - minutes, say. If I have a minute of conscious experience here, then I am annihilated, and either by accident or by design a copy of my brain just as it was at the moment of annihilation is made a trillion years later, which goes on to have another minute of conscious experience as if nothing remarkable had happened, would *that* qualify as two minutes of continuous conscious experience in my life? If so, where does causation enter into it to link the two minutes? Sure, the second minute is unlikely to come about unless some information is saved from the first minute and deliberate work put into making the copy, but *how* it comes about can't make any difference *once* it comes about. The mere fact that these two physical processes occur somewhere in the universe is enough to bring about two continuous minutes of consciousness. In fact, I don't see how the experiment I have described could possibly not give this result. You don't even need to be a computationalist or a functionalist: as long as the second copy has the right sort of mental experiences, whether due to God providing a replacement soul or the right sort of tiny black holes in the microtubules or whatever, then ipso facto, I will have two minutes of apparently continuous conscious experience.
> I suppose that you would assert that a first person experience was
> attached to this performance, a performance moving against a background
> of stars as the stage. Is that correct?
The question you are asking is in principle answerable by experiment: how finely can you divide up the physical processes which give rise to thought and still have continuous thought? You could teleport a subject nanometres to the left, then the same distance back to the right, repeating this at varying frequencies. We assume that the teleportation is as close as doesn't matter to instantaneous and that the resultant "vibration" in situ is not in itself noticeable to the subject. You have agreed in previous posts that the "regular" sort of teleportation we frequently discuss would not have much impact on the subject. If you performed this sort of vibrational teleportation in the kilohertz or megahertz range, would he notice anything strange happening to him? Would you notice anything strange talking to him?
> Next we begin a process of deconstruction. First, on one century's
> performance, there is trouble with the spotlight, and it's very dim
> although the audience can still see the show. But a few performances
> (centuries) later, the spotlight goes out altogether. Still, the
> audience knows from the notes passed out exactly what is happening.
> On another night, the audience fails to show up. Do these things
> really affect whether or not a first person experience attends the
No, provided that the audience did not interact with the brain on the basis of what they saw.
> In other performances, the spotlight dances all around, from a
> trillionth of a trillionth of a trillionth of a hundred trillionth
> of a second (about 10^-50 seconds) from your brain in midlife to
> your brain as an adolescent, then to your brain as a young adult,
> then to the geezer Stathis brain, and so on, completely wrecking
> the order. Now from what you wrote above about
> > it takes to run a human mind, and these moments
> > of consciousness randomly dispersed throughout the multiverse,
> > they would all connect up by virtue of their information content.
> one might surmise that you believe that the order that these frozen
> brains appear is irrelevant. (I happen to agree---my own view is
> that as soon as there was no longer causality connecting each
> frozen brain with another brain---that is, that no real computation
> was taking place---the first person experience no longer occurred.)
> But if I have surmised correctly, then you wouldn't care that the
> frozen brains were not only shown sometimes out of sequence, but
> that there did not have to be an audience, nor was the spatial
> relative locations of the brains relevant. They could be jumbled
> all over the cosmos.
I would *care* because it would be a nightmare, literally: I would not be able to interact with the physical universe or with anyone else, I would not be able to control where my thoughts took me, I would very quickly deteriorate into noise and die (which may be a blessing). At the moment, photons strike my retina, which causes certain impulses in my visual cortex, which I perceive as light. That's causality at work. If the same impulses occur in my cortex randomly, without the light stimulus, I could have exactly the same subjective experience, but it would be a hallucination, and my interactions with the world would suffer as a result. But if I take the subjective experience in isolation, it is *exactly* the same regardless of how it came about.
> But next, what about the neurons making up the brains? What would
> be lost if they too were dispersed through time and space? Finally,
> just when, if any time, would anything be lost: what if the neurons
> are themselves separated into atoms and dispersed?
We could imagine a brain divided up but each neurone is stimulated just as it would have been had the brain been whole; then, each neurone separated but stimulated just as it would have been were it still connected to its neighbours; and finally, each component of each neurone, down to atoms, separated but behaving just as it was when it was whole. We could attach ears and vocal cords with the appropriate nerves etc. and talk to the atomised brain. I see no reason why this thing shouldn't function as normal, and I see no way it could know it wasn't still in its cranial vault, given that we were censoring the information it was fed. If exactly the same arrangement of matter came into being by chance, there is a difference because (a) it's even less likely to happen that way than as a result of deliberate effort, and (b) we wouldn't be able to communicate with it, because it would be lost in the background noise unless we set it up ourselves, but from the point of view of the brain itself, how could it make any difference who made it as long as physically it was identical?
> Well, to me this is the ultimate reductio, because it means that
> among the dust in the vast, vast, vast volumes of the cosmos, each
> of your brain states already exists. (To me this is as absurd as
> some of Hilary Putnam's claims, or Greg Egan's in Permutation City.
> (For the record, Greg Egan made it clear in an interview that he
> does *not* necessarily believe in the notions presented in all his
Where was this Egan interview?
> The only place in all this chain of reasoning where it seems that
> first person experience could be lost is when one state no longer
> followed *causally* from a preceding state, or, in other words
> (in my opinion) when a true computation involving information
> flow no longer occurred.
> Your thoughts?
My tentative view is that unless self-awareness/cognition is somehow only possessed by creatures specially issued with souls, every physical process implements every computation, and this includes every conscious computation. Those conscious computations that are the result of causal laws, which includes the functioning of our own brains, evolve in a predictable way and are able to interact with their environment. Those that are based on noise are necessarily disconnected from anything other than their own thoughts, and rapidly (or instantaneously) devolve into nothing. So in a sense every possible observer moment or mental state exists, but only a tiny subset is able to give rise to persons or other recognisably sentient beings.
Be one of the first to try Windows Live Mail.
You received this message because you are subscribed to the Google Groups "Everything List" group.
To post to this group, send email to firstname.lastname@example.org
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at http://groups.google.com/group/everything-list
- RE: A calculus of personal identity Stathis Papaioannou
- (offlist) RE: A calculus of personal identity Lee Corbin
- Re: A calculus of personal identity John M
- Re: A calculus of personal identity Bruno Marchal
- RE: A calculus of personal identity Lee Corbin