let p, q be Element of CQC-WFF ; for x being bound_QC-variable st not x in still_not-bound_in p holds
( (All x,(p => q)) => (p => (All x,q)) is valid & (p => (All x,q)) => (All x,(p => q)) is valid )
let x be bound_QC-variable; ( not x in still_not-bound_in p implies ( (All x,(p => q)) => (p => (All x,q)) is valid & (p => (All x,q)) => (All x,(p => q)) is valid ) )
assume A1:
not x in still_not-bound_in p
; ( (All x,(p => q)) => (p => (All x,q)) is valid & (p => (All x,q)) => (All x,(p => q)) is valid )
hence
(All x,(p => q)) => (p => (All x,q)) is valid
by Lm17; (p => (All x,q)) => (All x,(p => q)) is valid
not x in still_not-bound_in (All x,q)
by Th5;
then
not x in still_not-bound_in (p => (All x,q))
by A1, Th7;
then A2:
(All x,((p => (All x,q)) => (p => q))) => ((p => (All x,q)) => (All x,(p => q))) is valid
by Lm17;
( All x,(((All x,q) => q) => ((p => (All x,q)) => (p => q))) is valid & (All x,(((All x,q) => q) => ((p => (All x,q)) => (p => q)))) => ((All x,((All x,q) => q)) => (All x,((p => (All x,q)) => (p => q)))) is valid )
by Th26, Th34, LUKASI_1:59;
then A3:
(All x,((All x,q) => q)) => (All x,((p => (All x,q)) => (p => q))) is valid
by CQC_THE1:104;
All x,((All x,q) => q) is valid
by Th26, CQC_THE1:105;
then
All x,((p => (All x,q)) => (p => q)) is valid
by A3, CQC_THE1:104;
hence
(p => (All x,q)) => (All x,(p => q)) is valid
by A2, CQC_THE1:104; verum