[extropy-chat] Indexical Uncertainty

[Robin Hanson]

At 11:42 PM 10/15/2006, Lee Corbin wrote:
> > 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.
>
>But what sense does such a counterfactual make (you *could be* Napoleon)?
>That's like saying that Soul #29230041608 could attach to Robin Hanson or
>it could attach to Napoleon Bonaparte.  As a good Bayesian, you should use
>all the information you have, but you *must* use the information 
>that makes you
>who you are. Everything else *you* know must be predicated up that first.

At 02:15 AM 10/16/2006, John K Clark wrote:
> > You seem to be rejecting the concept of indexical uncertainty
>
>What sort of index could you possibly provide to convince me that I am not
>me? ... The agent might have uncertainty about what Everett style
>universe he was now living in, but not that he is he.

At 03:01 AM 10/16/2006, Eugen* Leitl wrote:
> > The fact that I find myself as an individual in pre-Singularity
>
>Wherever you go, there you are. You're not an omniscient
>external observer, randomly picking items from the same
>reference class. You're only observing an infinitely self-biased
>sample of one: yourself.

Let's start with simple examples.   I might wake up and for a moment not be
able to remember whether it is Monday, when I can sleep in, or Tuesday,
when I need to get up early.   This is not uncertainty about the world, it is
uncertainty about who I am, whether I am Monday-Robin or Tuesday-Robin.

I might also have amnesia, permanent or temporary.  For example, I might
have been having a dream about my life as Lee Corbin, and so I might wake
up and for a moment not remember if I was really Robin Hanson or Lee Corbin.

When I ask "Am I Robin?" the "I" in this sentence cannot be by definition
equal to Robin, as then the claim would be true by definition.  If I 
am able to
be uncertain about this, it must be that "I" refers to something 
other than "Robin,"
so that it can be only a contingent fact about the world that "I" am "Robin."

If Lee could also have had a dream that confused him about whether he was
Lee or Robin, then when he asks "Am I Robin?" the "I" in his question must
refer to something different than the "I" when I ask the 
question.   So if we are
to be able to represent the uncertainty in both of these questions, I 
can't see
how to escape having things like "Soul #29230041608" in our language.




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