let p, q be Element of CQC-WFF ; :: thesis: (p 'or' q) => (('not' p) => q) in TAUT
(('not' p) => q) => (('not' p) => q) in TAUT by LUKASI_1:4;
hence (p 'or' q) => (('not' p) => q) in TAUT by Lm1; :: thesis: verum