let a be Int_position; :: thesis: for l being Nat holds not a in dom (Start-At (l,SCMPDS))
let l be Nat; :: thesis: not a in dom (Start-At (l,SCMPDS))
A1: dom (Start-At (l,SCMPDS)) = {(IC )} by FUNCOP_1:13;
assume a in dom (Start-At (l,SCMPDS)) ; :: thesis: contradiction
then a = IC by A1, TARSKI:def 1;
hence contradiction by SCMPDS_2:43; :: thesis: verum