reserve S for non empty non void ManySortedSign,
  A for MSAlgebra over S;
reserve A for non-empty MSAlgebra over S;
reserve S for non empty non void ManySortedSign,
  A for non-empty MSAlgebra over S,
  R for ManySortedRelation of the Sorts of A;

theorem Th46:
  for R being stable ManySortedRelation of A holds EqCl(R,A) is stable
proof
  let R be stable ManySortedRelation of A;
  let h be Endomorphism of A;
  let s be SortSymbol of S;
  let a,b be set;
  assume
A1: [a,b] in EqCl(R,A).s;
  then reconsider a, b as Element of A,s by ZFMISC_1:87;
  a,b are_convertible_wrt R.s by A1,Th42;
  then h.s.a, h.s.b are_convertible_wrt R.s by Th45;
  hence thesis by Th42;
end;
