>From: "Jesse Mazer" <[EMAIL PROTECTED]>
>>From: "Jacques Mallah" <[EMAIL PROTECTED]>
>>"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".)
>
>Well, I hope you'd agree that which observer-moment I am right now is not a
>"matter of definition," but a matter of fact.
Depends what you mean by that ...
>My opinion is that the global measure on all observer-moments is not
>telling us something like the "number of physical instantiations" of each
>one, but rather the probability of *being* one particular observer-moment
>vs. some other one.
No, if taken at face value that really doesn't make any sense at all.
There is no randomness in the multiverse.
On the other hand, it is proportional to the *effective*
"probability of being" one. In this case, "effective" refers to the role it
plays in Bayesian reasoning. The reason it plays that role is to maximize
the fraction of people who, using Bayesian reasoning, guess well. By
"people" here I mean what you would call "instantiations of OM's".
>I would be interested to hear what you think the measure means, though,
>since my version seems to require first-person facts which are separate
>from third-person facts (i.e., which observer-moment *I* am).
The measure is just the number of observer-moments (where I mean
different people count as different people) that see that type of
observation. It is really a measure on the characteristics of OM's, rather
than on OM's, since each O-M is counted equally. # of O-M = # of observers
* moments.
>In any case, I'm pretty sure there's room in a TOE for a "conditional
>probability" which would not be directly deducible from the global
>probability distribution. Suppose I have a large population of individuals,
>and I survey them on various personal characteristics, like height, IQ,
>age, etc. Using the survey results I can create a global probability
>function which tells me, for example, what the likelihood is that a random
>individualis more than 5 feet tall. But If I then want to find out the
>conditional probability that a given individual over 5 feet tall weighs
>more than 150 pounds, there is no way to deduce this directly given only
>the global probability distribution.
Sure there is, as you go on to say ...
>In this example it may be that p(A|B) = M(A and B) / M(B), but the point is
>that M(A and B) cannot be found simply by knowing M(A) and M(B).
Of course it can't, unless you know that A and B are independent. Why
the heck would you even think of trying?
The global measure is on the whole set of OM characteristics:
M(...,a,b,c,d,...). To find M(A), you have to set a = A and sum over all
possible values of b, c, d, etc.
The global measure has all the information, so to actually use it you
have to ignore most of that stuff by summing over irrelevant details.
>And a TOE could conceivably work other ways too. Suppose we have a large
>number of interconnected bodies of water, each flowing into one another at
>a constant rate so that the total amoung of water in any part stays
>constant over time. In that case you could have something like a "global
>measure" which would tell you the probability that a randomly selected
>water molecule will be found in a given body of water at a given time, but
>also a kind of conditional probability that a water molecule currently in
>river A will later be found in any one of the various other rivers that
>river A branches into. This would approximate the idea that my
>consciousness is in some sense "flowing" between different experiences,
>splitting and merging as it goes.
>Just as the path of a given molecule is determined by the geographical
>relationships between the various bodies of water, so the path of my
>conscious experience might be determined by some measure of the
>"continuity" between different observer-moments...even though an
>observer-moment corresponding to my brain 5 seconds from now and another
>one corresponding to your own brain at this very moment might have equal
>*global* measure, I would presumably be much more likely to flow into a
>future observer-moment which is more similar to my current one.
The appeal of that kind of model is based on the illusion that we can
remember past experiences. We can't remember past experiences at all,
actually. We only experience "memory" because of the _current_ way our
brains are structured. It's possible to "remember" things that never
happenned, not just a la "Total Recall" but even in simple cases like
swearing that you just parked in one place, but your car is on the other
side of th
