reserve i,j for Nat;

theorem Th2:
  for x being variable holds varcl vars x = vars x
  proof
    let x be variable; x in Vars; then
    consider A being Subset of Vars, j being Element of NAT such that
A1: x = [varcl A,j] & A is finite by ABCMIZ_1:18;
    vars x = varcl A by A1;
    hence thesis;
  end;
