Definition filterbase : (X → hProp) → hProp := λ A : X → hProp, (∃ B : X → hProp, base B × ∏ x, B x → A x).
Require Import UniMath.Foundations.Preamble. Require Import UniMath.MoreFoundations.Tactics. Require Import UniMath.MoreFoundations.PartA.