Section Upper_dim.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.
Definition upper_dim_axiom := forall A B C P Q : Tpoint,
P <> Q -> Cong A P A Q -> Cong B P B Q -> Cong C P C Q ->
(Bet A B C \/ Bet B C A \/ Bet C A B).
Definition all_coplanar_axiom := forall A B C D, Coplanar A B C D.

Lemma upper_dim_implies_perp2__col :
upper_dim_axiom ->
(forall X Y Z A B,
Perp X Y A B ->
Perp X Z A B ->
Col X Y Z).