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

theorem
  q => (q => r) in TAUT(A) implies q => r in TAUT(A)
proof
  (q => (q => r)) => (q => r) in TAUT(A) by Th10;
  hence thesis by CQC_THE1:46;
end;
