Theorem Rstar'_Rstar:  (x:A)(y:A)(Rstar' x y)->(Rstar x y).
Proof [x,y:A]
(unf_Rstar' [P:A->A->Prop](P x y)->(Rstar x y)
[h:(P:A->A->Prop)
(P x x)->((u:A)(R x u)->(Rstar u y)->(P x y))->(P x y)]
(h [a,a0:A](Rstar a a0) (Rstar_reflexive x) [u:A](Rstar_R x u y))).