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From: weemba@brahms.BERKELEY.EDU (Matthew P. Wiener)
Newsgroups: net.puzzle,net.philosophy,net.sci,net.religion
Subject: Newcomb's Paradox
Message-ID: <12518@ucbvax.BERKELEY.EDU>
Date: Fri, 21-Mar-86 05:06:42 EST
Article-I.D.: ucbvax.12518
Posted: Fri Mar 21 05:06:42 1986
Date-Received: Sat, 22-Mar-86 22:36:48 EST
Sender: usenet@ucbvax.BERKELEY.EDU
Reply-To: weemba@brahms.BERKELEY.EDU (Matthew P. Wiener)
Followup-To: net.puzzle
Organization: University of California, Berkeley
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Xref: watmath net.puzzle:1538 net.philosophy:4575 net.sci:625 net.religion:9749

I am presenting a famous dilemma originally proposed by the physicist
William Newcomb.  I think it can be of interest to the readers of all
the newsgroups I've posted to, because it touches on the nature of faith
and reason, but I am directing all followups to net.puzzle only.

In particular, I'd like to know if it has any bearing on the possibilities
of either perfect precognition or rational decision making.
-------------------------------------------------------------------------
The situation involves a being X.  X is precognizant.  In the first
version of the problem, X is perfect in this power.  If you like, X
is God.  In the second version, X is only partially precognizant, but
has a very very good track record--at least 99% accurate according to
all studies.

X is also very rich and completely honest.  X puts an unknown amount
of money in two boxes A and B.  X tells you that he put $1K (= one
thousand dollars) in box A.  X also tells you that he put either $0
or $1M (= one million dollars) in box B.  You are now given one chance
to earn some quick and easy money.  Your only options are
	(1) the one-boxer option:
		Open box B only.
	(2) the two-boxer option:
		Open box A and B both.
You are not going to be given a second chance nor a third option.  X
furthermore tells you that he put $1M in box B if X predicted you would
follow option (1) only.  He then tells you he put $0 in box B if he
predicted you would follow option (2) only, or if you end up deciding
to use a randomization device (other than, if you wish, your own free
will).

The question is, what do you pick, in either version?  And why?

Let me emphasize, there is no retroactive changing of the contents of
box B.  Either there is a million dollars waiting for you in box B or
there isn't.  There definitely is a thousand dollars waiting for you
in box A.

And if it all seems too simple to you, would it make any difference if
the boxes were transparent?

ucbvax!brahms!weemba	Matthew P Wiener/UCB Math Dept/Berkeley CA 94720