Definition isfinitedecsubset {X : UU} (f : X -> bool) (sx : isfinite X) : isfinite (hfiber f true) := hinhfun (finstructondecsubset f) sx.
Require Import UniMath.MoreFoundations.Tactics. Require Import UniMath.MoreFoundations.DecidablePropositions. Require Import UniMath.MoreFoundations.NegativePropositions. Require Import UniMath.MoreFoundations.Subtypes.