Re: decision theory papers

From: Brent Meeker <meekerdb.domain.name.hidden>
Date: Thu, 18 Apr 2002 16:15:48 -0700 (PDT)

On Thu, 18 Apr 2002, Wei Dai wrote:

> On Thu, Apr 18, 2002 at 02:08:56PM -0700, Brent Meeker wrote:
> > Why are you in principle unable to compute your own choices? Do you refer
> > to unable to predict or unable to enumerate or both?
>
> I mean there is no algorithm which your brain can implement, such that
> given the mathematical description of a universe and your place in it, it
> always correctly predicts your decision. The reason is that the decision
> you actually do make is going to be affected by the prediction. Whatever
> prediction the algorithm makes, the rest of your brain can decide to do
> something else after learning about the prediction.

I don't see this. You seem to be making a proof by contradiction - but I
don't see that it works. There is no contradiction is assuming that there
is an algorithm that correctly predicts your decision and then you make
that decision. You only arrive at an apparent contradiction because you
suppose the there is some left out part, "the rest of your brain", that
was not taken into account by the algorithm. This is what I meant by
incoherent. All that really follows is that *if* there were such an
algorithm you would necessarily do what it predicted. If the universe is
deterministic and computable, such an algorithm must exist. The only
conclusion I see is that if you executed this algorithm you would
loose the feeling of free will (of course you would have predicted this).

Brent Meeker
I have yet to see any problem, however complicated, which when you
looked at it in the right way, did not become still more complicated.
      --- Poul Anderson
Received on Thu Apr 18 2002 - 16:17:45 PDT