Definition carddneg (X : UU) (fx: isfinite X) : nat := pr1 (isfiniteimplisfinite0 X fx).
Require Import UniMath.MoreFoundations.Tactics. Require Import UniMath.MoreFoundations.DecidablePropositions. Require Import UniMath.MoreFoundations.NegativePropositions. Require Import UniMath.MoreFoundations.Subtypes.