let V be non empty set ; for C being Category
for a being Object of C st Hom C c= V holds
(hom?? (V,C)) ?- (a opp) = hom?- (V,a)
let C be Category; for a being Object of C st Hom C c= V holds
(hom?? (V,C)) ?- (a opp) = hom?- (V,a)
let a be Object of C; ( Hom C c= V implies (hom?? (V,C)) ?- (a opp) = hom?- (V,a) )
assume A1:
Hom C c= V
; (hom?? (V,C)) ?- (a opp) = hom?- (V,a)
A2:
id (a opp) = id a
by OPPCAT_1:71;
thus (hom?? (V,C)) ?- (a opp) =
(curry (hom?? C)) . (id a)
by A1, Def26, A2
.=
hom?- a
by Th56
.=
hom?- (V,a)
by A1, Def24
; verum