Nick Bostrom wrote:
>Bruno Marchal wrote:
>
>> I would propose to see ``observer-moment" as relative computational
>> states
>> of sufficiently reflexive universal machines.
>
>It seems reasonable that if brain A works twice as fast as brain B,
>then A will tend to have twice as many observer-moments per second as
>B. So observer-moments are pieces of subjective time, it seems.
You would be right if I'd have said that an ``observer moment" is
a relative computational state of a sufficiently reflexive
universal machine, *as known* by that machine, i.e. from the first
person point of view.
But for the measure problem, it seems to me that we must find
a measure on the set of third person 'relative' descriptions of
these 'relative' states. (Like Everett, as I interpret him).
>Nick Bostrom wrote:
>Here are three problems. Does anybody have any ideas how they
>should be resolved?
>
>1. What about a brain that is stuck for 10 years thinking the same
>thought, but at very high clockspeed - a navel-gazing Jupiterbrain?
>Is that one observer-moment or very many?
Here you meet again the 1/3-person points of view dichotomy.
If you really mean *exactly* the same thought, then it is ONE
observer-moment from the 1-person point of view of the observer.
(or ONE little bunch observer-moments because it is hard to even
talk of one 'train of thought'. I believe Russell Standish makes a
relevant remark here concerning the fact that we deal with sort of infinitesimals).
And from the 1-person POV the clock-speed doesn't change anything.
(POV = Point Of View)
>From the 3-person POV there are very many 'relative incarnations'
of that observer-moment.
The question is: does it change the probability that that poor
person will live that instant(°). I guess the answer is yes with ASSA
and no with RSSA.
With RSSA only relative 'bi(multi)furcation' makes the probability
higher. I 'd think.
(°) Oliver Sacks describes real similar cerebro-pathological case in
his book 'the man who took his wife for a hat'.
>2. Are highly clear, intelligent, intense observer-moments to be
>given more weight than dull ones?
I don't see any reason to give more weight to intelligent, intense observer-moments than dull ones.
Nor do I think "intelligent" and "intense" are linked. A dull person
could change the intensity of "consciousness" with some mushrooms
without changing (maybe even lowering) his intelligence or his
'clarity' of mind.
With RSSA weights are relative. I can imagine that the butterfly's
consciousness is very intense (from his 1-person POV). But the
probability of its experience is linked to the space of its personal
possible (computational) histories.
>Or is there a sharp cut-off where
>sentience goes from not having any observer-moments to having
>full-blown obsever-moments?
I doubt very much there is such sharp cut-off.
>Or does all sentience equally have
>observer-moments?
>
>From the 1-person point of view I guess it will depend on
the 'moment'.
My own 'observer-moment' are different in the morning and in the
evening. After or before coffee ...
These questions are like Nagel's "what is like to be a bat?"
>From comp these are unsoluble problem, although we can make
(hopefully correct) guesses.
>3. What about obsevers that are not readily separable? Human brains
>are quite distinct things so we might not be very familiar with this
>situation (though consider split-personalities and subconscious
>processing, and persons who have had their corpus callosum
>dissected), but could they not arise in artificial intellects? If
>consciousness need not always be unified, then how count the
>observer-moments?
>From a 1-person point of view consciousness is unified. But a brain
in abnormal (or even perhaps usual) state can vehiculated more than
one person with or without conflicts, with or without proper sharing
of 'history' memories, with or without control of the body, etc.
It is a theorem (with comp) that if we are machine we cannot know
which machine we are (we can only make bets on a level of substitution).
So, from a 1-person POV, there is no sense to try counting
the "real relative" observer-moment at that correct levels of
substitution. We can only guess through observations, or (as I do)
deduce from philosophical principle the 'geometry' of
the observer-moments.
Bruno
PS My chapter 5 of my thesis (URL below) present a way (*the* way ?)
to tackle formally (even arithmetically) such questions.
My chapter 5 = comp + the theetetical (platonic) definition of belief,
knowledge and my observation variants (the Z logics).
Of course (and unfortunately) the questions are transformed into
difficult mathematical questions :-(
Let us say it is a program for the next millenium :-)
Bruno MARCHAL Phone : +32 (0)2 6502711
Universite Libre Fax : +32 (0)2 6502715
de Bruxelles Prive : +32 (0)2 3439666
Avenue F.D. Roosevelt, 50 IRIDIA, CP 194/6
B-1050 BRUSSELS Email : marchal.domain.name.hidden
Belgium URL :
http://iridia.ulb.ac.be/~marchal
Received on Tue Sep 21 1999 - 03:46:00 PDT