(* Gabriel Braun April 2013 *)
Require Export GeoCoq.Tarski_dev.Ch12_parallel.
Section L13_1.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.
(** Pappus Desargues *)

Lemma flat_all_lea : forall A B C, A <> B -> C <> B -> Bet A B C -> forall P, P <> B -> LeA A B P A B C.