let A be QC-alphabet ; for x being bound_QC-variable of A
for p being Element of QC-WFF A holds
( bound_in (All (x,p)) = x & the_scope_of (All (x,p)) = p )
let x be bound_QC-variable of A; for p being Element of QC-WFF A holds
( bound_in (All (x,p)) = x & the_scope_of (All (x,p)) = p )
let p be Element of QC-WFF A; ( bound_in (All (x,p)) = x & the_scope_of (All (x,p)) = p )
All (x,p) is universal
;
then
All (x,p) = All ((bound_in (All (x,p))),(the_scope_of (All (x,p))))
by Th6;
hence
( bound_in (All (x,p)) = x & the_scope_of (All (x,p)) = p )
by Th5; verum