theorem Th17: :: MSUALG_8:17

for S being non empty non void ManySortedSign
for A being non-empty MSAlgebra over S
for i being Element of S
for X being Subset of (EqRelLatt the Sorts of A)
for B being Equivalence_Relation of the Sorts of A st B = "\/" X holds
B . i = "\/" ((EqRelSet (X,i)),(EqRelLatt ( the Sorts of A . i)))