let U1, U2 be Universal_Algebra; for h being Function of U1,U2 st U1,U2 are_similar holds
for o being OperSymbol of (MSSign U1) holds (MSAlg h) . (the_result_sort_of o) = h
let h be Function of U1,U2; ( U1,U2 are_similar implies for o being OperSymbol of (MSSign U1) holds (MSAlg h) . (the_result_sort_of o) = h )
assume A1:
U1,U2 are_similar
; for o being OperSymbol of (MSSign U1) holds (MSAlg h) . (the_result_sort_of o) = h
set f = MSAlg h;
let o be OperSymbol of (MSSign U1); (MSAlg h) . (the_result_sort_of o) = h
A2:
( the carrier' of (MSSign U1) = dom (signature U1) & the ResultSort of (MSSign U1) = (dom (signature U1)) --> 0 )
by MSUALG_1:def 8;
A3:
0 in {0}
by TARSKI:def 1;
thus (MSAlg h) . (the_result_sort_of o) =
(MSAlg h) . ( the ResultSort of (MSSign U1) . o)
by MSUALG_1:def 2
.=
(0 .--> h) . 0
by A1, A2, Def3, Th10
.=
h
by A3, FUNCOP_1:7
; verum