reserve f, g, h for Function;
reserve x, y, z, u, X for set,
  A for non empty set,
  n for Element of NAT,
  f for Function of X, X;
reserve f for c=-monotone Function of bool X, bool X,
  S for Subset of X;

theorem Th7:
  S c= f.S implies S c= gfp(X,f)
proof
  set H = {h where h is Subset of X : h c= f.h };
  assume S c= f.S;
  then S in H;
  hence thesis by ZFMISC_1:74;
end;
