let q, p be Element of CQC-WFF ; :: thesis: q => ((q => p) => p) in TAUT
( (('not' p) => q) => ((q => p) => p) in TAUT & ((('not' p) => q) => ((q => p) => p)) => (q => ((q => p) => p)) in TAUT ) by Lm11, Th6;
hence q => ((q => p) => p) in TAUT by CQC_THE1:82; :: thesis: verum