reserve A for QC-alphabet;
reserve p, q, r, s for Element of CQC-WFF(A);

theorem
  q in TAUT(A) implies ( p 'or' q ) in TAUT(A)
proof
  assume
A1: q in TAUT(A);
  q => ( p 'or' q ) in TAUT(A) by Th4;
  hence thesis by A1,CQC_THE1:46;
end;
