let x be bound_QC-variable; for S being Element of CQC-Sub-WFF
for xSQ being second_Q_comp of [S,x] st [S,x] is quantifiable & x in rng (RestrictSub x,(All x,(S `1 )),xSQ) holds
S_Bound (@ (CQCSub_All [S,x],xSQ)) = x. (upVar (RestrictSub x,(All x,(S `1 )),xSQ),(S `1 ))
let S be Element of CQC-Sub-WFF ; for xSQ being second_Q_comp of [S,x] st [S,x] is quantifiable & x in rng (RestrictSub x,(All x,(S `1 )),xSQ) holds
S_Bound (@ (CQCSub_All [S,x],xSQ)) = x. (upVar (RestrictSub x,(All x,(S `1 )),xSQ),(S `1 ))
let xSQ be second_Q_comp of [S,x]; ( [S,x] is quantifiable & x in rng (RestrictSub x,(All x,(S `1 )),xSQ) implies S_Bound (@ (CQCSub_All [S,x],xSQ)) = x. (upVar (RestrictSub x,(All x,(S `1 )),xSQ),(S `1 )) )
set S1 = CQCSub_All [S,x],xSQ;
assume that
A1:
[S,x] is quantifiable
and
A2:
x in rng (RestrictSub x,(All x,(S `1 )),xSQ)
; S_Bound (@ (CQCSub_All [S,x],xSQ)) = x. (upVar (RestrictSub x,(All x,(S `1 )),xSQ),(S `1 ))
A3:
CQCSub_All [S,x],xSQ = Sub_All [S,x],xSQ
by A1, Def6;
then A4:
(CQCSub_All [S,x],xSQ) `2 = xSQ
by A1, Th27;
A5:
(CQCSub_All [S,x],xSQ) `1 = All ([S,x] `2 ),(([S,x] `1 ) `1 )
by A1, A3, Th27;
then A6:
(CQCSub_All [S,x],xSQ) `1 = All x,(([S,x] `1 ) `1 )
by MCART_1:7;
then A7:
( (CQCSub_All [S,x],xSQ) `1 = All x,(S `1 ) & x = bound_in ((CQCSub_All [S,x],xSQ) `1 ) )
by MCART_1:7, QC_LANG2:8;
set finSub = RestrictSub (bound_in ((CQCSub_All [S,x],xSQ) `1 )),((CQCSub_All [S,x],xSQ) `1 ),((CQCSub_All [S,x],xSQ) `2 );
A8:
@ (CQCSub_All [S,x],xSQ) = CQCSub_All [S,x],xSQ
by SUBSTUT1:def 35;
(CQCSub_All [S,x],xSQ) `1 = All x,(([S,x] `1 ) `1 )
by A5, MCART_1:7;
then
bound_in ((CQCSub_All [S,x],xSQ) `1 ) = x
by QC_LANG2:8;
then
bound_in ((CQCSub_All [S,x],xSQ) `1 ) in rng (RestrictSub (bound_in ((CQCSub_All [S,x],xSQ) `1 )),((CQCSub_All [S,x],xSQ) `1 ),((CQCSub_All [S,x],xSQ) `2 ))
by A2, A4, A6, MCART_1:7;
then
S_Bound (@ (CQCSub_All [S,x],xSQ)) = x. (upVar (RestrictSub (bound_in ((CQCSub_All [S,x],xSQ) `1 )),((CQCSub_All [S,x],xSQ) `1 ),((CQCSub_All [S,x],xSQ) `2 )),(the_scope_of ((CQCSub_All [S,x],xSQ) `1 )))
by A8, SUBSTUT1:def 36;
hence
S_Bound (@ (CQCSub_All [S,x],xSQ)) = x. (upVar (RestrictSub x,(All x,(S `1 )),xSQ),(S `1 ))
by A4, A7, QC_LANG2:8; verum