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Re: [CL] Re: Decidability



Norbert,

A Skolem function is actually an unspecified
function.  If you have a statement such as

    For every prime number x, there exists
    a prime number y greater than x,

that implies that there exists one or more
possible functions from x to y.  In this case,
there is an uncountably infinite number of
such functions.  If you replace the variable
y with a Skolem function f(x), the symbol f
is merely a representative for any of those
possible functions, some of which are primitive
recursive and some of which are not.

But in any case, if a statement is decidable
before you replace any variables with Skolem
functions, it will still be decidable afterwards.

John