proposition: Corollary funcontrtwice { X : UU } (P: X-> X -> UU) (is: ∏ (x x':X), iscontr (P x x')) : iscontr (∏ (x x':X), P x x').
proof: Proof. intros. assert (is1: ∏ x:X, iscontr (∏ x':X, P x x')). - intro. apply (funcontr _ (is x)). - apply (funcontr _ is1). Defined.
imports: UniMath.Foundations.PartB