[extropy-chat] Doomsday argument

[Robin Hanson]

At 11:10 PM 10/15/2006, Lee Corbin wrote:
> >>"What would it be like for me if I were a bat" is, as you know, a 
> bad question.
> >>Likewise, we can't "find ourselves" as you write, in the 14th 
> century (unless
> >>someone had... simulations or hidden societies going on back then).
> >
> > I don't agree that it matters what your identity is or whether it 
> holds constant.
> > The issue is what beliefs are appropriate given the *info* available in a
> > situation.   That could include info, or lack of info, about any 
> aspect of your
> > identity [!], as well as info about anything else.    So it can 
> make sense to ask
> > what you should believe if you had the info a bat has, or what you should
> > believe if you had the info that people had in the 14th century.
>
>Yes, I could conceivably have the info that a bat has at a certain time
>and place. But I could not *be* a bat. That is, "I" could not have
>different info---contrary to what you write above---concerning the
>critical factors of my identity, the things that make me who I am.

The fact that you cannot be other than who you are does not at all imply
that you cannot be uncertain about who you are.   You can even be uncertain
about critical factors of your identity.   If is even possible to imagine that
you are uncertain about whether you are a human or a bat.

>The Doomsday Argument asks about chances of *being* an individual
>living over certain periods, and the point here is that almost all historical
>periods are inadmissable because you can't be anyone else.

It seems to me that one can imagine being uncertain about what historical
period one lives in.    Given such uncertainty, we can ask what reasonable
beliefs are about that.



Robin Hanson  rhanson at gmu.edu  http://hanson.gmu.edu
Associate Professor of Economics, George Mason University
MSN 1D3, Carow Hall, Fairfax VA 22030-4444
703-993-2326  FAX: 703-993-2323