let C be category; for o1, o2 being Object of (AllMono C)
for m being Morphism of o1,o2 st <^o1,o2^> <> {} holds
m is mono
let o1, o2 be Object of (AllMono C); for m being Morphism of o1,o2 st <^o1,o2^> <> {} holds
m is mono
let m be Morphism of o1,o2; ( <^o1,o2^> <> {} implies m is mono )
assume A1:
<^o1,o2^> <> {}
; m is mono
reconsider p1 = o1, p2 = o2 as Object of C by Def1;
reconsider p = m as Morphism of p1,p2 by A1, ALTCAT_2:33;
p is mono
by A1, Def1;
hence
m is mono
by A1, Th37; verum