The
ab notation makes it clear that
not and
or are dependent on one another and we can
therefore not use them as simultaneous indefinables.
Same objections in the case of apparent variables to
the
usual old indefinables, as in the
case of molecular functions.
The application of the
ab notation to apparent
variable propositions becomes clear if we consider that, for instance,
the proposition “for all x,
φx” is to be
true when
φx is true for all
x's and false when
φx is false for some
x's.
We see that
some and
all occur simultaneously in
the proper apparent variable notation.
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