let s be State of SCM+FSA; for I being parahalting Program of SCM+FSA st Initialized I c= s holds
ProgramPart s halts_on s
let I be parahalting Program of SCM+FSA; ( Initialized I c= s implies ProgramPart s halts_on s )
A1:
I +* (Start-At (0,SCM+FSA)) is halting
by Def3;
( Start-At (0,SCM+FSA) c= Initialized I & I c= Initialized I )
by FUNCT_4:26, SCMFSA6A:26;
then
( I +* (Start-At (0,SCM+FSA)) c= I \/ (Start-At (0,SCM+FSA)) & I \/ (Start-At (0,SCM+FSA)) c= Initialized I )
by FUNCT_4:30, XBOOLE_1:8;
then A2:
I +* (Start-At (0,SCM+FSA)) c= Initialized I
by XBOOLE_1:1;
assume
Initialized I c= s
; ProgramPart s halts_on s
then
I +* (Start-At (0,SCM+FSA)) c= s
by A2, XBOOLE_1:1;
hence
ProgramPart s halts_on s
by A1, EXTPRO_1:def 10; verum