Require Import Classical. Parameter causes : Prop -> Prop -> Prop. Conjecture wf : well_founded causes. Hint Resolve wf : core. Definition contingent (P : Prop) := exists Q, causes Q P. Definition neccessary (P : Prop) := ~ contingent P. Corollary GOD : exists G, neccessary G. apply NNPP. intros H. apply well_founded_ind with causes; auto. - intros x Hx. enough (Hg : exists G, neccessary G). contradiction. exists x. intros [y Hy]. contradiction (Hx y Hy). - exact True. Qed.