reserve i, x, I for set,
  A, B, M for ManySortedSet of I,
  f, f1 for Function;
reserve SF, SG for SubsetFamily of M;
reserve E, T for Element of Bool M;
reserve g, h for SetOp of M;

theorem :: CLOSURE:16
  E = M & g is reflexive implies E = g.E
proof
  assume
A1: E = M;
  assume g is reflexive;
  then
A2:   E c= g.E;
   g.E c= E by A1,PBOOLE:def 18;
 hence thesis by A2,PBOOLE:146;
end;
