FOM: Re: Kanovei's Picture

charles silver silver_1 at
Tue Apr 16 07:29:53 EDT 2002

    Of course, according to Leibniz's metaphysical picture of the world (and
every other possible world as well), each individual is unique or else there
would be no reason for it to exist.   (An extraneous element in any possible
world might be said, loosely speaking, to simply disappear from that world.
"Pop!")  I (sort of) recall an old paper of Max Black's (~1940?) in which he
formulated a two-element universe in which the two elements were numerically
distinct but identical in terms of all of their properties and relations.
I'm not sure whether his construction worked or not; my weak memory of this
is that he was assailed by various philosophers for making some fundamental
errors (or else for formulating so simplistic a world that nothing of merit
could be inferred from that world to any richer universe).   However, other
philosophers, apparently wishing to avoid the strain of interminable,
senseless disputes with Black, simply retreated to the position that there
was an additional relation Black had neglected, namely the one of being
*numerically* identical.   So, according to them, Black's two elements, a
and b, had all their *other* properties (and relations) in common, but 'Iaa'
held, yet 'Iab' did *not* hold.  Thus, it could still be maintained that
they were different objects.


More information about the FOM mailing list