let S be non empty non void ManySortedSign ; :: thesis: for A being MSAlgebra over S
for G being GeneratorSet of A
for B being MSSubset of A st G c= B holds
B is GeneratorSet of A

let A be MSAlgebra over S; :: thesis: for G being GeneratorSet of A
for B being MSSubset of A st G c= B holds
B is GeneratorSet of A

let G be GeneratorSet of A; :: thesis: for B being MSSubset of A st G c= B holds
B is GeneratorSet of A

let B be MSSubset of A; :: thesis: ( G c= B implies B is GeneratorSet of A )
B is MSSubset of (GenMSAlg B) by MSUALG_2:def 17;
then A1: B c= the Sorts of (GenMSAlg B) by PBOOLE:def 18;
assume G c= B ; :: thesis: B is GeneratorSet of A
then G c= the Sorts of (GenMSAlg B) by A1, PBOOLE:13;
then G is MSSubset of (GenMSAlg B) by PBOOLE:def 18;
then GenMSAlg G is MSSubAlgebra of GenMSAlg B by MSUALG_2:def 17;
then the Sorts of (GenMSAlg G) is MSSubset of (GenMSAlg B) by MSUALG_2:def 9;
then A2: the Sorts of (GenMSAlg G) c= the Sorts of (GenMSAlg B) by PBOOLE:def 18;
A3: the Sorts of (GenMSAlg G) = the Sorts of A by MSAFREE:def 4;
then the Sorts of (GenMSAlg B) is MSSubset of (GenMSAlg G) by MSUALG_2:def 9;
then the Sorts of (GenMSAlg B) c= the Sorts of (GenMSAlg G) by PBOOLE:def 18;
hence the Sorts of (GenMSAlg B) = the Sorts of A by A3, A2, PBOOLE:146; :: according to MSAFREE:def 4 :: thesis: verum