let MS be non empty trivial non void segmental ManySortedSign ; for A, B being non-empty MSAlgebra of MS st 1-Alg A = 1-Alg B holds
MSAlgebra(# the Sorts of A,the Charact of A #) = MSAlgebra(# the Sorts of B,the Charact of B #)
let A, B be non-empty MSAlgebra of MS; ( 1-Alg A = 1-Alg B implies MSAlgebra(# the Sorts of A,the Charact of A #) = MSAlgebra(# the Sorts of B,the Charact of B #) )
assume A1:
1-Alg A = 1-Alg B
; MSAlgebra(# the Sorts of A,the Charact of A #) = MSAlgebra(# the Sorts of B,the Charact of B #)
A2:
1-Alg B = UAStr(# (the_sort_of B),(the_charact_of B) #)
by MSUALG_1:def 19;
A3:
1-Alg A = UAStr(# (the_sort_of A),(the_charact_of A) #)
by MSUALG_1:def 19;
the Charact of A =
the charact of (1-Alg A)
by A3, MSUALG_1:def 18
.=
the Charact of B
by A1, A2, MSUALG_1:def 18
;
hence
MSAlgebra(# the Sorts of A,the Charact of A #) = MSAlgebra(# the Sorts of B,the Charact of B #)
by A4, PBOOLE:3; verum