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

[Ian Goddard]

Heartland wrote:

>> Literally: for all objects x and y, x is y if and 
>> only if for all properties P, P is a property of x 
>> if and only if P is a property of y. More simply: 
>> x is y just in case every property of x is a 
>> property of y and vice versa."

> 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.


 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. 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

 


 
____________________________________________________________________________________
Get your email and see which of your friends are online - Right on the New Yahoo.com 
(http://www.yahoo.com/preview)