let ll1, ll2 be FinSequence of QC-variables A; ( ex k being Nat ex P being QC-pred_symbol of k,A ex ll being QC-variable_list of k,A ex e being Element of vSUB A st
( ll1 = ll & S = Sub_P (P,ll,e) ) & ex k being Nat ex P being QC-pred_symbol of k,A ex ll being QC-variable_list of k,A ex e being Element of vSUB A st
( ll2 = ll & S = Sub_P (P,ll,e) ) implies ll1 = ll2 )
given k1 being Nat, P1 being QC-pred_symbol of k1,A, ll19 being QC-variable_list of k1,A, e1 being Element of vSUB A such that A2:
ll1 = ll19
and
A3:
S = Sub_P (P1,ll19,e1)
; ( for k being Nat
for P being QC-pred_symbol of k,A
for ll being QC-variable_list of k,A
for e being Element of vSUB A holds
( not ll2 = ll or not S = Sub_P (P,ll,e) ) or ll1 = ll2 )
A4:
S = [(P1 ! ll19),e1]
by A3, Th9;
given k2 being Nat, P2 being QC-pred_symbol of k2,A, ll29 being QC-variable_list of k2,A, e2 being Element of vSUB A such that A5:
ll2 = ll29
and
A6:
S = Sub_P (P2,ll29,e2)
; ll1 = ll2
A7:
( <*P2*> ^ ll29 = P2 ! ll29 & S `1 = <*P1*> ^ ll19 )
by A4, QC_LANG1:8;
A8:
S `1 is atomic
by A1, Th11;
A9:
S = [(P2 ! ll29),e2]
by A6, Th9;
then A10:
S `1 = P2 ! ll29
;
S `1 = P1 ! ll19
by A4;
then P1 =
the_pred_symbol_of (S `1)
by A8, QC_LANG1:def 22
.=
P2
by A10, A8, QC_LANG1:def 22
;
hence
ll1 = ll2
by A2, A5, A9, A7, FINSEQ_1:33; verum