> Sure, once they've grown. But right after birth? How can you tell any
> differences? If you
> cannot perform any personality or other cognitive test which
> establishes the the infant
> twins are not the same 'person' then for all intents and purposes they
> are the same
> person. Sure they will grow into different people, just as two clones
> will grow into
> different people, but at some point they are indistinguishable to
> science as being any
> different from each other. Therefore it is ok to kill one, so long as
> the other lives,
> since they are the same person.
> Mike Lorrey
i suspect this is something like the abortion problem you pose here. right after birth, even if they share the same genotypes, they have different phenotyping. because they don't evolve exactly in the same environment inside the mother, the babies are not in the same place inside, so they have different perceptions and are evolving differently. You have probably to go back, *at least*, just after the conception...
it's thus impossible to have the precondition of <<"If you cannot
perform any personality or other cognitive test which establishes the
the infant twins are not the same 'person' then for all intents and
purposes they are the same
I think the problem with Clark's proposition of identy is in the fact that you can't have two evolving systems sharing exactly the same (experiences, observations, environment). I fail to understand the improvements of a "identy notion " defined like that for a macro-system.