Metamath Proof Explorer


Theorem moanimv

Description: Introduction of a conjunct into an at-most-one quantifier. Version of moanim requiring disjoint variables, but fewer axioms. (Contributed by NM, 23-Mar-1995) Reduce axiom usage . (Revised by Wolf Lammen, 8-Feb-2023)

Ref Expression
Assertion moanimv
|- ( E* x ( ph /\ ps ) <-> ( ph -> E* x ps ) )

Proof

Step Hyp Ref Expression
1 ibar
 |-  ( ph -> ( ps <-> ( ph /\ ps ) ) )
2 1 mobidv
 |-  ( ph -> ( E* x ps <-> E* x ( ph /\ ps ) ) )
3 simpl
 |-  ( ( ph /\ ps ) -> ph )
4 3 exlimiv
 |-  ( E. x ( ph /\ ps ) -> ph )
5 2 4 moanimlem
 |-  ( E* x ( ph /\ ps ) <-> ( ph -> E* x ps ) )