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@nkaretnikov
Created April 27, 2015 00:41
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not_exists_dist
Theorem not_exists_dist :
excluded_middle ->
forall (X:Type) (P : X -> Prop),
~ (exists x, ~ P x) -> (forall x, P x).
Proof.
intros.
unfold excluded_middle in H.
unfold "~" in H0.
unfold "~" in H.
(* 1 subgoals, subgoal 1 (ID 72) *)
(* H : forall P : Prop, P \/ (P -> False) *)
(* X : Type *)
(* P : X -> Prop *)
(* H0 : (exists x : X, P x -> False) -> False *)
(* x : X *)
(* ============================ *)
(* P x *)
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