Curt Adams wrote:
> >> >... prefer a pleasurable meal this evening to one ten years ago ...
> >>I find this a nonsensical concept. Preferences for past actions have
> >>no meaning, as you can't undo them. ...
> >
> >Time machines are not logically impossible. Whether they are physically
> >impossible remains to be seen. So you should be able to make sense of
> >hypotheticals wherein you use a time machine to change past actions.
>
>I consider this kind of use of time machines logically impossible; it's a
>classic grandfather paradox.
Not every use of a time machine creates a grandfather paradox. We're
not talking about killing your previous self, just about giving them $1
more to spend back then. I see nothing paradoxical about that.
>In any case, such hypotheticals are
>impossible to calibratable; there's no way to determine if stated
>preferences mean anything and excellent reasons that past
>preferences would be inaccurate and inconsistent. There's sound
>evolutionary reasons for them to be meaningless side-effects of
>the real use of preferences, guiding action.
Even if we accept that our preferences about our past selves are
less accurate and consistent, and that they are side effects of
stronger evolutionary pressures, there still remains the question of
what those preferences are and what they imply.
Take music as an example. You might say that we evolved a taste for
music as a side effect of evolutionary pressures to show off various
mental abilities, and now that we have so many other ways to show
off mental abilities, or that we have less need to do so, there is no
*real* use of or need for music. But even if this is true, many of
us just like music, and policy analysis should take that into account.
Robin Hanson rhanson@gmu.edu http://hanson.gmu.edu
Asst. Prof. Economics, George Mason University
MSN 1D3, Carow Hall, Fairfax VA 22030-4444
703-993-2326 FAX: 703-993-2323
This archive was generated by hypermail 2b30 : Mon May 28 2001 - 09:50:19 MDT