;; IVY operation: MODEL
;;
;; With basis S and W, show that not all combinators have fixed points.

(and (= (a (a (a (S) x) y) z)
	(a (a x z) (a y z)))
     (= (a (a (W) x) y)
	(a (a x y) y))
     
     (not (all f (exists y (= (a f y) y)))))
