reserve U0 for Universal_Algebra,
  U1 for SubAlgebra of U0,
  o for operation of U0;

theorem Th11:
  for U0 being with_const_op Universal_Algebra for U1 be
SubAlgebra of U0 for a be set holds a is Element of Constants(U0) implies a in
  the carrier of U1
proof
  let U0 be with_const_op Universal_Algebra;
  let U1 be SubAlgebra of U0;
  let a be set;
A1: Constants(U0) is Subset of U1 by UNIALG_2:15;
  assume a is Element of Constants(U0);
  hence thesis by A1,TARSKI:def 3;
end;
