Section Tarski_is_a_Coinc_theory_for_col.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.
Definition diff : arity Tpoint 2 := fun A B : Tpoint => A <> B.
Definition col : arity Tpoint 3 := Col.

Lemma col_3 : forall (COL : cartesianPower Tpoint 3) (DIFF : cartesianPower Tpoint 2),
pred_conj col COL DIFF -> app diff DIFF -> app col COL.