let S be non empty non void bool-correct 4,1 integer BoolSignature ; for X being non-empty ManySortedSet of the carrier of S
for T being b1,S -terms all_vars_including inheriting_operations free_in_itself vf-free integer VarMSAlgebra over S
for C being bool-correct 4,1 integer image of T
for u being ManySortedFunction of FreeGen T, the Sorts of C holds (\true T) value_at (C,u) = TRUE
let X be non-empty ManySortedSet of the carrier of S; for T being X,S -terms all_vars_including inheriting_operations free_in_itself vf-free integer VarMSAlgebra over S
for C being bool-correct 4,1 integer image of T
for u being ManySortedFunction of FreeGen T, the Sorts of C holds (\true T) value_at (C,u) = TRUE
let T be X,S -terms all_vars_including inheriting_operations free_in_itself vf-free integer VarMSAlgebra over S; for C being bool-correct 4,1 integer image of T
for u being ManySortedFunction of FreeGen T, the Sorts of C holds (\true T) value_at (C,u) = TRUE
let C be bool-correct 4,1 integer image of T; for u being ManySortedFunction of FreeGen T, the Sorts of C holds (\true T) value_at (C,u) = TRUE
let u be ManySortedFunction of FreeGen T, the Sorts of C; (\true T) value_at (C,u) = TRUE
consider f being ManySortedFunction of T,C such that
A1:
( f is_homomorphism T,C & u = f || (FreeGen T) )
by MSAFREE4:46;
FreeGen T is_transformable_to the Sorts of C
by MSAFREE4:21;
then
doms u = FreeGen T
by MSSUBFAM:17;
then consider f being ManySortedFunction of T,C, Q being GeneratorSet of T such that
A2:
( f is_homomorphism T,C & Q = doms u & u = f || Q & (\true T) value_at (C,u) = (f . the bool-sort of S) . (\true T) )
by A1, AOFA_A00:def 21;
set o = In (( the connectives of S . 1), the carrier' of S);
A3:
( In (( the connectives of S . 1), the carrier' of S) = the connectives of S . 1 & the_arity_of (In (( the connectives of S . 1), the carrier' of S)) = {} & the_result_sort_of (In (( the connectives of S . 1), the carrier' of S)) = the bool-sort of S )
by Th11;
then
Args ((In (( the connectives of S . 1), the carrier' of S)),T) = {{}}
by Th21;
then reconsider p = {} as Element of Args ((In (( the connectives of S . 1), the carrier' of S)),T) by TARSKI:def 1;
( dom (f # p) = {} & dom p = {} )
by A3, MSUALG_3:6;
then A4:
p = f # p
;
(f . the bool-sort of S) . (\true T) =
\true C
by A4, A2, A3
.=
TRUE
by AOFA_A00:def 32
;
hence
(\true T) value_at (C,u) = TRUE
by A2; verum