[extropy-chat] Identity (was: Survival tangent)

[Heartland]

> "Ian Goddard" <iamgoddard at yahoo.com> Wrote:
>> the definition of 'identity' in logic matches
>> Leibniz's Identity of Indiscernibles.

John K Clark:
> Leibniz's  Identity Of Indiscernibles is the idea that if you exchange the
> position of two things and there  is no change in the system then the
> two things are the same. If I place you (the copy) and the original an
> equal distance from the center of a symmetrical room so you see the
> same things and then instantly swap your bodies position with the
> original then neither you nor the original nor any outside observer
> could detect the slightest change.

Then I'm afraid you don't really understand Leibniz's law. Regardless of the
arrangement, you can always come up with *at least one arbitrary* property
(measurement of the distance from a non-equidistant point, for example) with
respect to which two material things are going to be different; a sufficient
evidence for assigning different identities. Just because the copy subjectively
"feels" the same doesn't influence the fact that objectively it isn't and never
will be identical to the original as this would violate the law of conservation of
mass/energy. I basically agree with what Ian and Randall told you so far.

Slawomir