let i be Instruction of SCMPDS ; ( InsCode i = 1 implies not i is parahalting )
consider s being State of SCMPDS such that
A1:
for a being Int_position holds s . a = 2
by SCMPDS_2:73;
assume
InsCode i = 1
; not i is parahalting
then consider a being Int_position such that
A2:
i = return a
by SCMPDS_2:36;
assume
i is parahalting
; contradiction
then reconsider Li = Load i as parahalting Program of SCMPDS ;
set pi = stop Li;
set Ii = Initialized (stop Li);
set s1 = s +* (Initialized (stop Li));
(s +* (Initialized (stop Li))) . (DataLoc ((s +* (Initialized (stop Li))) . a),RetIC ) =
s . (DataLoc ((s +* (Initialized (stop Li))) . a),RetIC )
by Th19
.=
2
by A1
;
then A3: (Exec i,(s +* (Initialized (stop Li)))) . (IC SCMPDS ) =
(abs 2) + 2
by A2, SCMPDS_2:70
.=
2 + 2
by ABSVALUE:def 1
.=
4
;
set C1 = Comput (ProgramPart (s +* (Initialized (stop Li)))),(s +* (Initialized (stop Li))),1;
Initialized (stop Li) c= s +* (Initialized (stop Li))
by FUNCT_4:26;
then A4:
IC (Comput (ProgramPart (s +* (Initialized (stop Li)))),(s +* (Initialized (stop Li))),1) in dom (stop Li)
by SCMPDS_4:def 9;
0 in dom (Initialized (stop Li))
by Th13;
then A5: (s +* (Initialized (stop Li))) . 0 =
(Initialized (stop Li)) . 0
by FUNCT_4:14
.=
i
by Th13
;
A6:
card (stop Li) = 2
by Th8;
Y:
(ProgramPart (s +* (Initialized (stop Li)))) /. (IC (s +* (Initialized (stop Li)))) = (s +* (Initialized (stop Li))) . (IC (s +* (Initialized (stop Li))))
by AMI_1:150;
Comput (ProgramPart (s +* (Initialized (stop Li)))),(s +* (Initialized (stop Li))),(0 + 1) =
Following (ProgramPart (s +* (Initialized (stop Li)))),(Comput (ProgramPart (s +* (Initialized (stop Li)))),(s +* (Initialized (stop Li))),0 )
by AMI_1:14
.=
Following (ProgramPart (s +* (Initialized (stop Li)))),(s +* (Initialized (stop Li)))
by AMI_1:13
.=
Exec i,(s +* (Initialized (stop Li)))
by A5, Th18, FUNCT_4:26, Y
;
hence
contradiction
by A3, A4, A6, SCMPDS_4:1; verum