Metamath Proof Explorer


Theorem gblacfnac2d

Description: If G is a global choice function, then the Axiom of Choice holds. This is gblacfnacd expressed using CHOICE . (Contributed by BTernaryTau, 25-Sep-2026)

Ref Expression
Hypotheses gblacfnac2d.1
|- ( ph -> G Fn _V )
gblacfnac2d.2
|- ( ph -> A. z ( z =/= (/) -> ( G ` z ) e. z ) )
Assertion gblacfnac2d
|- ( ph -> CHOICE )

Proof

Step Hyp Ref Expression
1 gblacfnac2d.1
 |-  ( ph -> G Fn _V )
2 gblacfnac2d.2
 |-  ( ph -> A. z ( z =/= (/) -> ( G ` z ) e. z ) )
3 1 2 gblacfnacd
 |-  ( ph -> A. x E. f ( f Fn x /\ A. z e. x ( z =/= (/) -> ( f ` z ) e. z ) ) )
4 dfac4
 |-  ( CHOICE <-> A. x E. f ( f Fn x /\ A. z e. x ( z =/= (/) -> ( f ` z ) e. z ) ) )
5 3 4 sylibr
 |-  ( ph -> CHOICE )