let p, q be Element of CQC-WFF ; :: thesis: ( p '&' q in TAUT implies q in TAUT )
assume A1: p '&' q in TAUT ; :: thesis: q in TAUT
(p '&' q) => q in TAUT by Th21;
hence q in TAUT by A1, CQC_THE1:46; :: thesis: verum