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NOT_FORALL_CONV

Conv.NOT_FORALL_CONV : conv

Moves negation inwards through a universal quantification.

When applied to a term of the form ~(!x.P), the conversion NOT_FORALL_CONV returns the theorem:

   |- ~(!x.P) = ?x.~P

It is irrelevant whether x occurs free in P.

Failure

Fails if applied to a term not of the form ~(!x.P).

See also

Conv.EXISTS_NOT_CONV, Conv.FORALL_NOT_CONV, Conv.NOT_EXISTS_CONV