reserve x,y,z,X for set,
  T for Universe;

theorem Th5:
  for R be non empty RelStr, T be non empty 1-sorted, p be Element
  of T, q be Element of ConstantNet(R,p) holds ConstantNet(R,p).q = p
proof
  let R be non empty RelStr, T be non empty 1-sorted, p be Element of T, q be
  Element of ConstantNet(R,p);
  thus ConstantNet(R,p).q = ((the carrier of ConstantNet(R,p)) --> p).q by Def5
    .= p;
end;
