let S be feasible ManySortedSign ; for S' being Subsignature of S
for T being ManySortedSign
for f, g being Function st f,g form_morphism_between S,T holds
f | the carrier of S',g | the carrier' of S' form_morphism_between S',T
let S' be Subsignature of S; for T being ManySortedSign
for f, g being Function st f,g form_morphism_between S,T holds
f | the carrier of S',g | the carrier' of S' form_morphism_between S',T
let T be ManySortedSign ; for f, g being Function st f,g form_morphism_between S,T holds
f | the carrier of S',g | the carrier' of S' form_morphism_between S',T
let f, g be Function; ( f,g form_morphism_between S,T implies f | the carrier of S',g | the carrier' of S' form_morphism_between S',T )
A1:
g | the carrier' of S' = g * (id the carrier' of S')
by RELAT_1:94;
( id the carrier of S', id the carrier' of S' form_morphism_between S',S & f | the carrier of S' = f * (id the carrier of S') )
by Def2, RELAT_1:94;
hence
( f,g form_morphism_between S,T implies f | the carrier of S',g | the carrier' of S' form_morphism_between S',T )
by A1, PUA2MSS1:30; verum