let p, q, r be Element of CQC-WFF ; :: thesis: ( p => (q => r) is valid implies (p => q) => (p => r) is valid )
assume A1: p => (q => r) is valid ; :: thesis: (p => q) => (p => r) is valid
(p => (q => r)) => ((p => q) => (p => r)) is valid by Th54;
hence (p => q) => (p => r) is valid by A1, CQC_THE1:104; :: thesis: verum