[extropy-chat] Personal Identity Bis

Randall Randall randall at randallsquared.com
Fri Apr 13 22:30:13 UTC 2007

On Apr 13, 2007, at 12:52 PM, Eugen Leitl wrote:
> On Fri, Apr 13, 2007 at 12:34:12PM -0400, Randall Randall wrote:
>> we can't, then how do we know we have two?  Taken literally,
>> the statement "two systems are indistinguishable" is a logical
>> contradiction.
> Physics doesn't care a fig about what a monkey thinks is a  
> contradiction.
> http://en.wikipedia.org/wiki/Identical_particles

It seems obvious that this doesn't apply to complex
macroscopic objects like DVDs and people, any more than
the fact that electrons have no "wet" property can be
applied to a bucket of water.  There are a lot of firm
statements I'm willing to make about a cup of coffee
on my desk that I freely admit don't apply to the
particles that make up the coffee.  Nor do I think
that this means the coffee is somehow not wet, or
the cup is somehow not green.

In any case, my statement quoted above stands even
with this, since "indistinguishable", here, seems to
mean, "...as long as we take care to lose track of
which is which by putting them near enough to have
their wavefunctions overlap."  It seems clear that
DVDs, coffee cups, and people will never overlap in
this way by accident, even if we had examples of all
three that had identical duplicates.

> http://www.iop.org/EJ/abstract/0305-4470/13/4/008
> http://www.engin.umich.edu/~CRE/03chap/html/transition/

So far, I don't know enough math to understand the
relevance of the third link, or to understand the
second link at all from the available abstract.

Randall Randall <randall at randallsquared.com>
"This is a fascinating question, right up there with whether rocks
fall because of gravity or being dropped, and whether 3+5=5+3
because addition is commutative or because they both equal 8."
   - Scott Aaronson

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