Definition Concyclic_gen A B C D :=
  Concyclic A B C D \/ (Col A B C /\ Col A B D /\ Col A C D /\ Col B C D).Definition concy : arity Tpoint 4 := Concyclic_gen.

Lemma concyclic_gen_2341 : forall A B C D, Concyclic_gen A B C D -> Concyclic_gen B C D A.