(**)
intros. red. intros i j H. split. intro x. red. intro H1. elim H1. intros y H2
H3. elim(eq_nat_dec i 0). intro a. rewrite a in H2. simpl in H2. elim(
eq_nat_dec j 0). intuition. intro bb. rewrite(if_r _ _ _(eq_nat_dec j 0)(
Complement _ A)(if eq_nat_dec j 1 then A else Empty_set _)bb)in H3. elim(
eq_nat_dec j 1). intro aaa. rewrite aaa in H3. simpl in H3. auto. intro bbb.
rewrite(if_r _ _ _(eq_nat_dec j 1)A(Empty_set _)bbb)in H3. elim H3.
(**)
intro b. rewrite(if_r _ _ _(eq_nat_dec i 0)(Complement _ A)(if eq_nat_dec i 1
then A else Empty_set _)b)in H2. elim(eq_nat_dec i 1). intro aa. rewrite aa in
H2. simpl in H2. elim(eq_nat_dec j 0). intro aaa. rewrite aaa in H3. simpl in
H3. auto. intro bbb. rewrite(if_r _ _ _(eq_nat_dec j 0)(Complement _ A)(if
eq_nat_dec j 1 then A else Empty_set _)bbb)in H3. elim(eq_nat_dec j 1).
intuition. intro bbbb. rewrite(if_r _ _ _(eq_nat_dec j 1)A(Empty_set _)bbbb) in
H3. elim H3. intro bb. rewrite(if_r _ _ _(eq_nat_dec i 1)A(Empty_set _)bb)in H2
. elim H2. Qed.

Lemma simple_P5:
forall(U:Type)(A:Ensemble U),
simple_1 _ 2(fun i:nat=>INR i)(fun i:nat=>if eq_nat_dec i 0 then Complement _ A
else if eq_nat_dec i 1 then A else Empty_set _).