let x1, x2, y1, y2 be set ; for E being non empty set
for F1, F2 being Subset of (E ^omega)
for TS1 being non empty transition-system of F1
for TS2 being non empty transition-system of F2 st the carrier of TS1 = the carrier of TS2 & the Tran of TS1 = the Tran of TS2 & x1,x2 ==>* y1,y2,TS1 holds
x1,x2 ==>* y1,y2,TS2
let E be non empty set ; for F1, F2 being Subset of (E ^omega)
for TS1 being non empty transition-system of F1
for TS2 being non empty transition-system of F2 st the carrier of TS1 = the carrier of TS2 & the Tran of TS1 = the Tran of TS2 & x1,x2 ==>* y1,y2,TS1 holds
x1,x2 ==>* y1,y2,TS2
let F1, F2 be Subset of (E ^omega); for TS1 being non empty transition-system of F1
for TS2 being non empty transition-system of F2 st the carrier of TS1 = the carrier of TS2 & the Tran of TS1 = the Tran of TS2 & x1,x2 ==>* y1,y2,TS1 holds
x1,x2 ==>* y1,y2,TS2
let TS1 be non empty transition-system of F1; for TS2 being non empty transition-system of F2 st the carrier of TS1 = the carrier of TS2 & the Tran of TS1 = the Tran of TS2 & x1,x2 ==>* y1,y2,TS1 holds
x1,x2 ==>* y1,y2,TS2
let TS2 be non empty transition-system of F2; ( the carrier of TS1 = the carrier of TS2 & the Tran of TS1 = the Tran of TS2 & x1,x2 ==>* y1,y2,TS1 implies x1,x2 ==>* y1,y2,TS2 )
assume A1:
( the carrier of TS1 = the carrier of TS2 & the Tran of TS1 = the Tran of TS2 )
; ( not x1,x2 ==>* y1,y2,TS1 or x1,x2 ==>* y1,y2,TS2 )
assume
x1,x2 ==>* y1,y2,TS1
; x1,x2 ==>* y1,y2,TS2
then
==>.-relation TS1 reduces [x1,x2],[y1,y2]
by Def6;
then
==>.-relation TS2 reduces [x1,x2],[y1,y2]
by A1, Th34;
hence
x1,x2 ==>* y1,y2,TS2
by Def6; verum