Re: Existence, Self-identity and Uniqueness.

Hi

Owen wrote:
Jan Burse wrote:
Wrong again.
The introduction of "the x:Fx" does not render FOL= inconsistent at
all, unles you foolishly assume that non-referring descriptions are
values of the indidvidual variable.
I don't do that, why do you persist in doing that??

I was on purpose using some foolishly substitutions.
Someone has to do sometimes foolishly things to
show inconsistency, even in the precence of initially
innocent concepts.

I did this to show you that you are not strictly
working in FOL=. Because FOL= does not distinguish
between foolishly and non foolishly substitutions.

How do you bar foolishly substitutions from FOL=?
How do you control the following reasoning step,
which works in FOL= (even in FOL without =):

forall x A(x)
-------------
A(t)

Note again A is a formula. So we could also rewrite
the step as follows:

forall x A
----------
A[x/t]

Here A[x/t] denotes the result of substituting t for
x in the formula A. How do you control this, and still
claim you have FOL= at hand?

Bye

.

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