Theorem exmoeu2 2067

Description: Existence implies "at most one" is equivalent to uniqueness. (Contributed by NM, 5-Apr-2004.)

Assertion

Ref	Expression
exmoeu2	|- ( E. x ph -> ( E* x ph <-> E! x ph ) )

Proof of Theorem exmoeu2

Step	Hyp	Ref	Expression
1		eu5 2066	. 2 |- ( E! x ph <-> ( E. x ph /\ E* x ph ) )
2	1	baibr 915	1 |- ( E. x ph -> ( E* x ph <-> E! x ph ) )

Syntax hints:   -> wi 4   <-> wb 104   E.wex 1485   E!weu 2019   E*wmo 2020

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528

This theorem depends on definitions:  df-bi 116  df-nf 1454  df-sb 1756  df-eu 2022  df-mo 2023

This theorem is referenced by:  n0mmoeu  3431  fneu  5302