End T10_1.
Section T10_2D.
Context `{T2D:Tarski_2D}.

Lemma hilbert_s_version_of_pasch_2D : forall A B C P Q,
~ Col C Q P -> ~ Col A B P -> BetS A Q B ->
exists X, Col P Q X /\ (BetS A X C \/ BetS B X C).