Section Aristotle.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.
(** This proof is inspired by The elementary Archimedean axiom in absolute geometry, by Victor Pambuccian *)
(** This proof is inspired by Several topics from geometry, by Franz Rothe *)

Lemma aristotle__obtuse_case_elimination :
aristotle_s_axiom ->
~ hypothesis_of_obtuse_saccheri_quadrilaterals.