NOT_FORALL_CONV : conv
STRUCTURE
Conv
SYNOPSIS
Moves negation inwards through a universal quantification.
DESCRIPTION
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).
SEEALSO
EXISTS_NOT_CONV, FORALL_NOT_CONV, NOT_EXISTS_CONV
HOL  Kananaskis-13