On Wed, Jul 11, 2012 at 2:32 PM, doug foxvog <doug@xxxxxxxxxx>
On Tue, July 10, 2012 22:02, Chris Menzel wrote:
>> Consider the planet Venus in each of the Sci-Fi novels in which theIt depends upon the definition of the individual.
>> planet is described - it can have different properties,
>> therefore is in fact a different individual.
> That is *far* from clear. Suppose in one story it simply lacks a single
> grain of sand that it actually has. I'm certainly not inclined to say it
> is a different individual.
Well, that was pretty much exactly my point, although you've expressed it a bit more carefully. What I was responding to was the suggestion that it was somehow obvious a priori that if x and y have different properties at different times or in different worlds, then x ≠ y. There are certainly accounts of individuals on which that is not true.
Just like Theseus's ship.
Is Venus the same individual today that it was last year? It has different
mass, grains of interstellar dust that it didn't have then, and has lost
hydrogen from its atmosphere.
The Venus in any Sci-Fi novel is far more similar in properties to the Venus
that recently transited the Sun than my current properties are to those
of the Doug Foxvog of 50 years ago. If that is the basis for determining
whether something is a different individual, i and that Doug
Foxvog are certainly two different individuals.
-- doug foxvog