FW: FIN Again (was: Re: James Higgo)
-Original Message- From: Jacques Mallah [mailto:[EMAIL PROTECTED]] I've explained that in other posts, but as you see, the idea is indeed mathematically incoherent - unless you just mean the conditional effective probability which a measure distribution defines by definition. And _that_ one, of course, leads to a finite expectation value for ones's observed age (that is, no immortality). Although I have other objections to the quantum theory of immortality, I still don't see how the sampling argument refutes it. Because (as I've said elsewhere) you don't know what a typical observer is. If the QTI is correct then a typical observer moment may *well* be someone who is 10^32 years old wondering why all the other protons have decayed except the ones in his body. But you have no way to find that out *except* by reaching that age yourself, because it's very very very very (keep typing very for another couple of weeks) unlikely that you will meet up with a typical observer who isn't yourself. Charles
RE: FIN Again (was: Re: James Higgo)
-Original Message- From: Jacques Mallah [mailto:[EMAIL PROTECTED]] I've explained that in other posts, but as you see, the idea is indeed mathematically incoherent - unless you just mean the conditional effective probability which a measure distribution defines by definition. And _that_ one, of course, leads to a finite expectation value for ones's observed age (that is, no immortality). I've just realised that according to the Bayesian argument, the chances of someone with an infinite world-line being ANY specific age are infinitesimal. (It also makes the chances of me being the age I am pretty infinitesimal too, come to think of it). That would seem to indicate that the Bayesian argument *assumes* that infinite world-lines (and possibly infinite anythings) are impossible. Sorry I took so long to spot that objection to the SSA argument, which I will call (4). Charles
Re: FIN Again (was: Re: James Higgo)
From: Jesse Mazer [EMAIL PROTECTED] I don't understand your objection. It seems to me that it is perfectly coherent to imagine a TOE which includes both a universal objective measure on the set of all observer-moments and also a relative conditional probability which tells me what the probability is I'll have experience B in the future if I'm having experience A right now. You is just a matter of definition. As for the conditional effective probability of an observation with characteristics A given that it includes characteristics B, p(A|B), that is automatically defined as p(A|B) = M(A and B) / M(B). There is no room to have a rival relative conditional probability. (E.g. A = I think I'm in the USA at 12:00 today, B=I think I'm Bob.) In statistics we have both absolute and conditional probability, so what's wrong with having the same thing in a TOE? In fact there is no choice but to have conditional probability - as long as it's the one that the absolute measure distribution automatically defines. I suppose one objection might be that once we have an objective measure, we understand everything we need to know about why I find myself having the types of experiences I do Indeed so. and that defining an additional conditional probability measure on the set of all observer-moments would be purely epiphenomenal and inelegant. Is that what your problem with the idea is? It's not just inelegant. It's impossible, if by additional you mean one that's not the automatic one. self-sampling assumption--what does it mean to say that I should reason as if I had an equal probability of being any one of all possible observer-moments? It means - and I admit it does take a little thought here - _I want to follow a guessing procedure that, in general, maximizes the fraction of those people (who use that procedure) who get the right guess_. (Why would I want a more error-prone method?) So I use Bayesian reasoning with the best prior available, the uniform one on observer-moments, which maximizes the fraction of observer-moments who guess right. No soul-hopping in that reasoning, I assure you. if I am about to step into a machine that will replicate one copy of me in heaven and one copy in hell, then as I step into the imaging chamber I will be in suspense about where I will find myself a moment from now, and if the conditional probability of each possible future observer-moment is 50% given my current observer-moment, then I will interpret that as a 50/50 chance that I'm about to experience torture or bliss. That depends on the definition of you. In any case, one copy will be happy (the one partying with the succubi in hell) and the other will be sad (the one stuck hanging out with Christians). So your utility function should be about even. I assume you'd care about both future copies at that point. Surely you agree that there is nothing *mathematically* incoherent about defining both absolute and conditional probability measures on the set of all observer-moments. So what's your basis for calling the idea crazy? I've explained that in other posts, but as you see, the idea is indeed mathematically incoherent - unless you just mean the conditional effective probability which a measure distribution defines by definition. And _that_ one, of course, leads to a finite expectation value for ones's observed age (that is, no immortality). - - - - - - - Jacques Mallah ([EMAIL PROTECTED]) Physicist / Many Worlder / Devil's Advocate I know what no one else knows - 'Runaway Train', Soul Asylum My URL: http://hammer.prohosting.com/~mathmind/ _ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp
Re: FIN Again (was: Re: James Higgo)
From: [EMAIL PROTECTED] Jacques Mallah writes: The problem comes when some people consider death in this context. I'll try to explain the insane view on this, but since I am not myself insane I will probably not do so to the satisfaction of those that are. I have mixed feelings about this line of reasoning, but I can offer some arguments in favor of it. I guess you mean in favor of FIN. How about against it too, since you have mixed feelings? The insane view however holds that the mind of the killed twin somehow leaps into the surviving twin at the moment he would have been killed. Thus, except for the effect on other people who might have known the twins, the apparent death is of no consequence. It's not that the mind leaps. That would imply that minds have location, wouldn't it? And spatial limits? But that notion doesn't work well. Mind is not something that is localized in the universe in the way that physical objects are. You can't pin down the location of a mind. Where in our brains is mind located? In the glial cells? In the neurons? The whole neuron, or just the synapse? It doesn't make sense to imagine that you can assign a numerical value to each point in the brain which represents its degree of mind-ness. Location is not a property of mind. A computationalist would say that the mind is due to the functioning of the brain, and thus is located where the parts that function are. But this is totally irrelevant. Suffice it to say that a mind is associated with that brain, while a different mind would be associated with a different brain. Hence we cannot speak of minds leaping. I remind you that _I_ never said they leap, could leap, or that such a thing is logically possible at all. I said only that the insane hold such a view, which many posters on this list do. Whatever they may mean by what they say, the effect is best described as saying they think minds leap. It makes more sense to think of mind as a relational phenomenon, like greater than or next to, but enormously more complicated. In that sense, if there are two identical brains, then they both exhibit the same relational properties. That means that the mind is the same in both brains. It's not that there are two minds each located in a brain, but rather that all copies of that brain implement the mind. Nope. That make no (0) sense at all. Sure, you could _define_ a mind to be some computation, as you seem to want, rather than being a specific implementation of that computation. But that's a rather silly definition, since it's a specific implementation that would be associated with conscious thinking of a particular brain, and thus with measure. Of course, even a twin who dies could never have the same computation as one that lived, since HALT is obviously a significant difference in the computation. Further support for this model can be found by considering things from the point of view of that mind. Let it consider the question, which brain am I in at this time? Which location in the universe do I occupy? There is no way for the mind to give a meaningful, unique response to this question. There's no way to know for sure, you mean. OK, I agree with that. You can still guess with high confidence. In any case, there's still a fact of the matter, regardless of whether you know that fact. Any answer will be both wrong and right. That makes no sense. The answer will be either wrong XOR right, for a particular mind; but you can't know for sure which of those minds is you. Hence you use indexical Bayesian reasoning or SSA. In this model, if the number of brains increases or decreases, the mind will not notice, it will not feel a change. Surviving minds won't notice a change. Dead minds won't feel a thing, which is the reason death sucks. No introspection will reveal the number of implementations of itself that exist in a universe or a multiverse. True, although with the SSA you can make some reasonable guesses. This is only dangerous if the belief is wrong, of course. The contrary belief could be said to be dangerous in its way, if it were wrong as well. (For example, it might lead to an urgent desire to build copies.) Even supposing the logical belief to be wrong - what's so dangerous about building copies? In any case, that would require a lot more tech than we have. I have repeated pointed out the obvious consequence that if that were true, then a typical observer would find himself to be much older than the apparent lifetime of his species would allow; the fact that you do not find yourself so old gives their hypothesis a probability of about 0 that it is the truth. However, they hold fast to their incomprehensible beliefs. This is a different argument and has nothing to do with the idea of leaping, which is mostly what I want to take issue with. Sure it has to do with it, because it proves