[extropy-chat] Identity (Survival tangent)

[Heartland]

S:
>> What you describe is, of course, Leibniz's law. "1"
>> and "1" are different instances of "1" since the
>> first "1" has a property of being to the left
>> of "and" while the other "1" has a property of
>> being to the right of "and". Multiple instances of
>> anything are "automatically" different.

Ian:
> Right, the definition of 'identity' in logic matches
> Leibniz's Identity of Indiscernibles. And if we're
> talking about 'identity', our conclusions should
> derive from its logical definition. Doing so shows
> that if x and y are identical, then all the properties
> of x and of y are identical and all the relations of x
> to z and of y to z are identical.

*nods*

Ian:
> But as I believe
> I've shown, due to physical reality, all the
> properties and relations of copies (be they copies of
> brains or computer files) are not identical. Indeed,
> the fact that 'copies' is as a plural term denotes
> that there are differences between them. ~Ian

Correct! That this is so is indeed "due to physical reality" as Leibniz's law is 
basically a necessary consequence of the law of conservation of mass/energy. In the 
above I would only replace "all the properties" with "some properties." Obviously, 
it would be sufficient to point to a single inconsistent property to show that two 
things were not identical.

Slawomir

P.S. For some reason only 1 out of your last 5 messages found its way to my inbox. 
I could find the other four only in the archives.