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Re: Fwd: SUO Quo Vadis



Phil,

Yes, I agree:

 > Of course this depends on what "describe" means. The
 > phrase "the real numbers" describes all the real numbers,
 > not just a countable subset.

I was using the word "describe" to continue the terminology
that Avril adopted.  I should have used the word "specify"
or "identify" to indicate that there is no finite statement
that can pick out a particular x out of an uncountable set
-- except for our familiar examples of pi, e, the solutions
to algebraic equations (such as the square root of 2), etc.

But there is a way to make the point using the word "describe":

    For almost all real numbers x, there is no finite statement
    S(x) that can describe x in a way that distinguishes x from
    infinitely many other real numbers for which S is also true.

(The term "almost all" means all but a countable subset.)

John