reserve n,i,j,k for Nat;
reserve T for TuringStr,
  s for All-State of T;

theorem Th40:
  for s,t being TuringStr, x be State of s holds [ x, the InitS of
  t ] in UnionSt(s,t)
proof
  let s,t be TuringStr,x be State of s;
  set q0=the InitS of t, A= [: the FStates of s, { q0 } :];
  reconsider q=q0 as Element of { q0 } by TARSKI:def 1;
  [ x, q ] in A;
  hence thesis by XBOOLE_0:def 3;
end;
