Let emptyset : set := Empty. Let elem : set->set->prop := In. Let notelem : set->set->prop := fun a A => ~(In a A). Let pow : set->set := Power. Let unions : set->set := Union. Let union : set->set->set := binunion. Let cons : set -> set -> set := fun x X => binunion {x} X. Let xor : prop -> prop -> prop := fun p q => (p \/ q) /\ ~(p /\ q). Let pair : set -> set -> set := fun a b => {{a}, {a, b}}. Let fst : set -> set := fun p => Eps_i (fun a => exists b, p = pair a b). Let snd : set -> set := fun p => Eps_i (fun b => exists a, p = pair a b). Let nor : prop -> prop -> prop := fun p q => ~(p \/ q) . Definition ni := fun x0 x1 : set => (elem x1 x0). Fact setext : (forall A B,(((forall a,(((elem a A)<->(elem a B))))->(A = B)))). Admitted. Theorem neq_witness : (forall A B,(((A <> B)->(exists c,((xor((elem c A)/\~((elem c B))) (~((elem c A))/\(elem c B)))))))). Admitted. Definition subseteq := fun A B: set => (forall a,(((elem a A)->(elem a B)))). Definition is_subset := fun x0 x1 : set => (subseteq x0 x1). Definition supseteq := fun x0 x1 : set => (subseteq x1 x0). Theorem subseteq_refl : (forall A,((subseteq A A))). Admitted. Theorem subseteq_antisymmetric : (forall A B,((((subseteq A B)/\(subseteq B A))->(A = B)))). Admitted. Theorem elem_subseteq : (forall a A B,((((elem a A)/\(subseteq A B))->(elem a B)))). Admitted. Theorem not_in_subseteq : (forall A B c,((((subseteq A B)/\(notelem c B))->(notelem c A)))). Admitted. Theorem subseteq_transitive : (forall A B C,((((subseteq A B)/\(subseteq B C))->(subseteq A C)))). Admitted. Definition subset := fun A B: set => ((subseteq A B)/\(A <> B)). Theorem subset_irrefl : (forall A,(~((subset A A)))). Admitted. Theorem subset_transitive : (forall A B C,((((subseteq A B)/\(subseteq B C))->(subseteq A C)))). Admitted. Theorem subset_witness : (forall A B,(((subset A B)->(exists b,(((elem b B)/\(notelem b A))))))). Admitted. Definition family_of_subsets := fun x0 x1 : set => (forall A,(((elem A x0)->(subseteq A x1)))). Fact notin_emptyset : (forall a,((notelem a (emptyset)))). Admitted. Definition inhabited := fun A: set => (exists a,((elem a A))). Definition empty := fun x0 : set => ~((inhabited x0)). Theorem empty_eq : (forall x y,((((empty x)/\(empty y))->(x = y)))). Admitted. Theorem emptyset_subseteq : (forall a,((subseteq (emptyset) a))). Admitted. Theorem subseteq_emptyset_iff : (forall A,(((subseteq A (emptyset))<->(A = (emptyset))))). Admitted. Definition disjoint := fun A B: set => ~((exists a,(((elem a A)/\(elem a B))))). Definition notmeets := fun x0 x1 : set => (disjoint x0 x1). Definition meets := fun x0 x1 : set => ~((disjoint x0 x1)). Theorem disjoint_symmetric : (forall A B,(((disjoint A B)->(disjoint B A)))). Admitted. Fact in_cons : (forall x y X,(((elem x (cons y X))<->((x = y)\/(elem x X))))). Admitted. Theorem in_cons_left : (forall x X,((elem x (cons x X)))). Admitted. Theorem in_cons_right : (forall y X x,(((elem y X)->(elem y (cons x X))))). Admitted. Theorem upair_intro_left : (forall a b,((elem a (cons a (cons b (emptyset)))))). Admitted. Theorem upair_intro_right : (forall b a,((elem b (cons a (cons b (emptyset)))))). Admitted. Theorem upair_elim : (forall c a b,(((elem c (cons a (cons b (emptyset))))->((a = c)\/(b = c))))). Admitted. Theorem upair_iff : (forall c a b,(((elem c (cons a (cons b (emptyset))))<->((a = c)\/(b = c))))). Admitted. Theorem singleton_intro : (forall a,((elem a (cons a (emptyset))))). Admitted. Theorem singleton_elim : (forall a b,(((elem a (cons b (emptyset)))->(a = b)))). Admitted. Theorem singleton_iff : (forall a b,(((elem a (cons b (emptyset)))<->(a = b)))). Admitted. Definition subsingleton := fun x0 : set => (forall a b,((((elem a x0)/\(elem b x0))->(a = b)))). Theorem singleton_inhabited : (forall a,((inhabited (cons a (emptyset))))). Admitted. Theorem singleton_iff_inhabited_subsingleton : (forall A a,((((subsingleton A)/\(elem a A))->(A = (cons a (emptyset)))))). Admitted. Theorem singleton_subset_intro : (forall a C,(((elem a C)->(subseteq (cons a (emptyset)) C)))). Admitted. Theorem singleton_subset_elim : (forall a C,(((subseteq (cons a (emptyset)) C)->(elem a C)))). Admitted. Fact unions_iff_exists : (forall z X,(((elem z (unions X))<->(exists Y,(((elem Y X)/\(elem z Y))))))). Admitted. Theorem unions_intro : (forall A B C,((((elem A B)/\(elem B C))->(elem A (unions C))))). Admitted. Theorem unions_emptyset : ((unions (emptyset)) = (emptyset)). Admitted. Theorem unions_family : (forall F X,(((family_of_subsets F X)->(subseteq (unions F) X)))). Admitted. Definition closedunderunions := fun x0 : set => (forall M,(((is_subset M x0)->(elem (unions M) x0)))). Definition inters := fun A : set => {x :e ((unions A))|(forall a,(((elem a A)->(elem x a))))}. Theorem inters_iff_forall : (forall z X,(((elem z (inters X))<->((inhabited X)/\(forall Y,(((elem Y X)->(elem z Y)))))))). Admitted. Theorem inters_intro : (forall C A,((((inhabited C)/\(forall B,(((elem B C)->(elem A B)))))->(elem A (inters C))))). Admitted. Theorem inters_destr : (forall A C B,((((elem A (inters C))/\(elem B C))->(elem A B)))). Admitted. Theorem inters_greatest : (forall A C,((((inhabited A)/\(forall a,(((elem a A)->(subseteq C a)))))->(subseteq C (inters A))))). Admitted. Theorem subseteq_inters_iff : (forall A C,(((inhabited A)->((subseteq C (inters A))<->(forall a,(((elem a A)->(subseteq C a)))))))). Admitted. Theorem inters_subseteq_elem : (forall B A,(((elem B A)->(subseteq (inters A) B)))). Admitted. Theorem inters_singleton : (forall a,(((inters (cons a (emptyset))) = a))). Admitted. Theorem inters_emptyset : ((inters (cons (emptyset) (emptyset))) = (emptyset)). Admitted. Fact union_iff : (forall a A B,(((elem a (union A B))<->((elem a A)\/(elem a B))))). Admitted. Theorem union_intro_left : (forall c A B,(((elem c A)->(elem c (union A B))))). Admitted. Theorem union_intro_right : (forall c B A,(((elem c B)->(elem c (union A B))))). Admitted. Theorem union_comm : (forall A B,(((union A B) = (union B A)))). Admitted. Theorem union_assoc : (forall A B C,(((union (union A B) C) = (union A (union B C))))). Admitted. Theorem union_idempotent : (forall A,(((union A A) = A))). Admitted. Theorem subseteq_union_iff : (forall A B C,(((subseteq (union A B) C)<->((subseteq A C)/\(subseteq B C))))). Admitted. Theorem union_upper_left : (forall A B,((subseteq A (union A B)))). Admitted. Theorem union_upper_right : (forall B A,((subseteq B (union A B)))). Admitted. Theorem union_subseteq_union : (forall A C B D,((((subseteq A C)/\(subseteq B D))->(subseteq (union A B) (union C D))))). Admitted. Theorem union_emptyset : (forall A,(((union A (emptyset)) = A))). Admitted. Theorem union_emptyset_intro : (forall A B,((((A = (emptyset))/\(B = (emptyset)))->((union A B) = (emptyset))))). Admitted. Theorem union_emptyset_elim_left : (forall A B,((((union A B) = (emptyset))->(A = (emptyset))))). Admitted. Theorem union_emptyset_elim_right : (forall A B,((((union A B) = (emptyset))->(B = (emptyset))))). Admitted. Theorem union_absorb_subseteq_left : (forall A B,(((subseteq A B)->((union A B) = B)))). Admitted. Theorem union_absorb_subseteq_right : (forall A B,(((subseteq A B)->((union B A) = B)))). Admitted. Theorem union_eq_self_implies_subseteq : (forall A B,((((union A B) = B)->(subseteq A B)))). Admitted. Theorem unions_cons : (forall b A,(((unions (cons b A)) = (union b (unions A))))). Admitted. Theorem union_cons : (forall b A C,(((union (cons b A) C) = (cons b (union A C))))). Admitted. Theorem union_absorb_left : (forall A B,(((union A (union A B)) = (union A B)))). Admitted. Theorem union_absorb_right : (forall A B,(((union (union A B) B) = (union A B)))). Admitted. Theorem union_comm_left : (forall A B C,(((union A (union B C)) = (union B (union A C))))). Admitted. Definition closedunderunion := fun x0 : set => (forall U V,((((elem U x0)/\(elem V x0))->(elem (union U V) x0)))). Definition inter := fun A B : set => {a :e (A)|(elem a B)}. Theorem inter_intro : (forall c A B,((((elem c A)/\(elem c B))->(elem c (inter A B))))). Admitted. Theorem inter_elim_left : (forall c A B,(((elem c (inter A B))->(elem c A)))). Admitted. Theorem inter_elim_right : (forall c A B,(((elem c (inter A B))->(elem c B)))). Admitted. Theorem inter_as_inters : (forall A B,(((inters (cons A (cons B (emptyset)))) = (inter A B)))). Admitted. Theorem inter_comm : (forall A B,(((inter A B) = (inter B A)))). Admitted. Theorem inter_assoc : (forall A B C,(((inter (inter A B) C) = (inter A (inter B C))))). Admitted. Theorem inter_idempotent : (forall A,(((inter A A) = A))). Admitted. Theorem inter_subseteq : (forall A B,((subseteq (inter A B) A))). Admitted. Theorem inter_emptyset : (forall A,(((inter A (emptyset)) = (emptyset)))). Admitted. Theorem inter_absorb_supseteq_right : (forall A B,(((subseteq A B)->((inter A B) = A)))). Admitted. Theorem inter_absorb_supseteq_left : (forall A B,(((subseteq A B)->((inter B A) = A)))). Admitted. Theorem inter_eq_left_implies_subseteq : (forall A B,((((inter A B) = A)->(subseteq A B)))). Admitted. Theorem subseteq_inter_iff : (forall C A B,(((subseteq C (inter A B))<->((subseteq C A)/\(subseteq C B))))). Admitted. Theorem inter_lower_left : (forall A B,((subseteq (inter A B) A))). Admitted. Theorem inter_lower_right : (forall A B,((subseteq (inter A B) B))). Admitted. Theorem inter_absorb_left : (forall A B,(((inter A (inter A B)) = (inter A B)))). Admitted. Theorem inter_absorb_right : (forall A B,(((inter (inter A B) B) = (inter A B)))). Admitted. Theorem inter_comm_left : (forall A B C,(((inter A (inter B C)) = (inter B (inter A C))))). Admitted. Definition closedunderinter := fun x0 : set => (forall U V,((((elem U x0)/\(elem V x0))->(elem (inter U V) x0)))). Theorem inter_distrib_union : (forall x y z,(((inter x (union y z)) = (union (inter x y) (inter x z))))). Admitted. Theorem union_distrib_inter : (forall x y z,(((union x (inter y z)) = (inter (union x y) (union x z))))). Admitted. Theorem union_inter_assoc_intro : (forall C A B,(((subseteq C A)->((union (inter A B) C) = (inter A (union B C)))))). Admitted. Theorem union_inter_assoc_elim : (forall A B C,((((union (inter A B) C) = (inter A (union B C)))->(subseteq C A)))). Admitted. Theorem union_inter_crazy : (forall A B C,(((union (union (inter A B) (inter B C)) (inter C A)) = (inter (inter (union A B) (union B C)) (union C A))))). Admitted. Theorem inters_distrib_union : (forall A B,((((inhabited A)/\(inhabited B))->((inters (union A B)) = (inter (inters A) (inters B)))))). Admitted. Definition setminus := fun A B : set => {a :e (A)|~((elem a B))}. Theorem setminus_intro : (forall a A B,((((elem a A)/\(notelem a B))->(elem a (setminus A B))))). Admitted. Theorem setminus_elim_left : (forall a A B,(((elem a (setminus A B))->(elem a A)))). Admitted. Theorem setminus_elim_right : (forall a A B,(((elem a (setminus A B))->(notelem a B)))). Admitted. Theorem setminus_emptyset : (forall x,(((setminus x (emptyset)) = x))). Admitted. Theorem emptyset_setminus : (forall x,(((setminus (emptyset) x) = (emptyset)))). Admitted. Theorem setminus_self : (forall x,(((setminus x x) = (emptyset)))). Admitted. Theorem setminus_setminus : (forall x y,(((setminus x (setminus x y)) = (inter x y)))). Admitted. Theorem double_relative_complement : (forall y x,(((subseteq y x)->((setminus x (setminus x y)) = y)))). Admitted. Theorem setminus_inter : (forall x y z,(((setminus x (inter y z)) = (union (setminus x y) (setminus x z))))). Admitted. Theorem setminus_union : (forall x y z,(((setminus x (union y z)) = (inter (setminus x y) (setminus x z))))). Admitted. Theorem inter_setminus : (forall x y z,(((inter x (setminus y z)) = (setminus (inter x y) (inter x z))))). Admitted. Theorem difference_with_proper_subset_is_inhabited : (forall A B,(((subset A B)->(inhabited (setminus B A))))). Admitted. Theorem setminus_subseteq : (forall B A,((subseteq (setminus B A) B))). Admitted. Theorem subseteq_setminus : (forall C A B,((((subseteq C A)/\((inter C B) = (emptyset)))->(subseteq C (setminus A B))))). Admitted. Theorem subseteq_implies_setminus_supseteq : (forall A B C,(((subseteq A B)->(supseteq (setminus C A) (setminus C B))))). Admitted. Theorem setminus_absorb_right : (forall A B,((((inter A B) = (emptyset))->((setminus A B) = A)))). Admitted. Theorem setminus_eq_emptyset_iff_subseteq : (forall A B,((((setminus A B) = (emptyset))<->(subseteq A B)))). Admitted. Theorem subseteq_setminus_cons_intro : (forall B A C c,((((subseteq B (setminus A C))/\(notelem c B))->(subseteq B (setminus A (cons c C)))))). Admitted. Theorem subseteq_setminus_cons_elim : (forall B A c C,(((subseteq B (setminus A (cons c C)))->((subseteq B (setminus A C))/\(notelem c B))))). Admitted. Theorem setminus_cons : (forall A a B,(((setminus A (cons a B)) = (setminus (setminus A (cons a (emptyset))) B)))). Admitted. Theorem setminus_cons_flip : (forall A a B,(((setminus A (cons a B)) = (setminus (setminus A B) (cons a (emptyset)))))). Admitted. Theorem setminus_disjoint : (forall A B,(((inter A (setminus B A)) = (emptyset)))). Admitted. Theorem setminus_partition : (forall A B,(((subseteq A B)->((union A (setminus B A)) = B)))). Admitted. Theorem subseteq_union_setminus : (forall A B,((subseteq A (union B (setminus A B))))). Admitted. Theorem double_complement : (forall A B C,((((subseteq A B)/\(subseteq B C))->((setminus B (setminus C A)) = A)))). Admitted. Theorem double_complement_union : (forall A B,(((setminus (union A B) (setminus B A)) = A))). Admitted. Theorem setminus_eq_inter_complement : (forall A C B,((((subseteq A C)/\(subseteq B C))->((setminus A B) = (inter A (setminus C B)))))). Admitted. Fact pair_eq_iff : (forall a b aprime bprime,((((pair a b) = (pair aprime bprime))<->((a = aprime)/\(b = bprime))))). Admitted. Fact pair_neq_emptyset : (forall a b,(((pair a b) <> (emptyset)))). Admitted. Fact pair_neq_fst : (forall a b,(((pair a b) <> a))). Admitted. Fact pair_neq_snd : (forall a b,(((pair a b) <> b))). Admitted. Theorem triple_eq_iff : (forall a b c aprime bprime cprime,((((pair a (pair b c)) = (pair aprime (pair bprime cprime)))<->(((a = aprime)/\(b = bprime))/\(c = cprime))))). Admitted. Fact fst_eq : (forall a b,(((fst (pair a b)) = a))). Admitted. Fact snd_eq : (forall a b,(((snd (pair a b)) = b))). Admitted. Theorem pair_eq_pair_of_proj : (forall a b,(((pair a b) = (pair (fst (pair a b)) (snd (pair a b)))))). Admitted. Definition times := fun A B : set => ReplSep2 (A)(fun dummyVar => B)(fun a b => True)(fun a b => (pair a b)). Theorem times_tuple_elim : (forall x y X Y,(((elem (pair x y) (times X Y))->((elem x X)/\(elem y Y))))). Admitted. Theorem times_tuple_intro : (forall x X y Y,((((elem x X)/\(elem y Y))->(elem (pair x y) (times X Y))))). Admitted. Theorem times_empty_left : (forall Y,(((times (emptyset) Y) = (emptyset)))). Admitted. Theorem times_empty_right : (forall X,(((times X (emptyset)) = (emptyset)))). Admitted. Theorem times_empty_iff : (forall X Y,(((empty (times X Y))<->((empty X)\/(empty Y))))). Admitted. Theorem fst_type : (forall c A B,(((elem c (times A B))->(elem (fst c) A)))). Admitted. Theorem snd_type : (forall c A B,(((elem c (times A B))->(elem (snd c) B)))). Admitted. Theorem times_elem_is_tuple : (forall p X Y,(((elem p (times X Y))->(exists x y,(((elem x X)/\((elem y Y)/\(p = (pair x y))))))))). Admitted. Theorem times_proj_elim : (forall p X Y,(((elem p (times X Y))->((elem (fst p) X)/\(elem (snd p) Y))))). Admitted. Theorem cons_subseteq_intro : (forall x X Y,((((elem x X)/\(subseteq Y X))->(subseteq (cons x Y) X)))). Admitted. Theorem cons_subseteq_elim : (forall x Y X,(((subseteq (cons x Y) X)->((elem x X)/\(subseteq Y X))))). Admitted. Theorem cons_subseteq_iff : (forall x Y X,(((subseteq (cons x Y) X)<->((elem x X)/\(subseteq Y X))))). Admitted. Theorem subseteq_cons_right : (forall C B a,(((subseteq C B)->(subseteq C (cons a B))))). Admitted. Theorem subseteq_cons_self : (forall X y,((subseteq X (cons y X)))). Admitted. Definition remove_point := fun x0 x1 : set => (setminus x1 (cons x0 (emptyset))). Theorem subseteq_cons_intro_left : (forall a C B,((((elem a C)/\(subseteq (remove_point a C) B))->(subseteq C (cons a B))))). Admitted. Theorem subseteq_cons_intro_right : (forall C B a,(((subseteq C B)->(subseteq C (cons a B))))). Admitted. Theorem subseteq_cons_elim : (forall C a B,(((subseteq C (cons a B))->((subseteq C B)\/((elem a C)/\(subseteq (remove_point a C) B)))))). Admitted. Theorem subseteq_cons_iff : (forall C a B,(((subseteq C (cons a B))<->((subseteq C B)\/((elem a C)/\(subseteq (remove_point a C) B)))))). Admitted. Theorem remove_point_eq_setminus_singletong : (forall a B,(((remove_point a B) = (setminus B (cons a (emptyset)))))). Admitted. Theorem union_eq_cons : (forall a B,(((union (cons a (emptyset)) B) = (cons a B)))). Admitted. Theorem cons_comm : (forall a b C,(((cons a (cons b C)) = (cons b (cons a C))))). Admitted. Theorem cons_absorb : (forall a A,(((elem a A)->((cons a A) = A)))). Admitted. Theorem cons_remove : (forall a A,(((elem a A)->((cons a (setminus A (cons a (emptyset)))) = A)))). Admitted. Theorem cons_idempotent : (forall a B,(((cons a (cons a B)) = (cons a B)))). Admitted. Theorem inters_cons : (forall B a,(((inhabited B)->((inters (cons a B)) = (inter a (inters B)))))). Admitted. Definition powerset_of := fun x0 : set => (pow x0). Fact pow_iff : (forall B A,(((elem B (pow A))<->(subseteq B A)))). Admitted. Theorem powerset_intro : (forall A B,(((subseteq A B)->(elem A (pow B))))). Admitted. Theorem powerset_elim : (forall A B,(((elem A (pow B))->(subseteq A B)))). Admitted. Theorem powerset_bottom : (forall A,((elem (emptyset) (pow A)))). Admitted. Theorem powerset_top : (forall A,((elem A (pow A)))). Admitted. Theorem unions_subseteq_of_powerset_is_subseteq : (forall B A,(((is_subset B (pow A))->(subseteq (unions B) A)))). Admitted. Theorem unions_powerset : (forall A,(((unions (pow A)) = A))). Admitted. Theorem inters_powerset : (forall A,(((inters (pow A)) = (emptyset)))). Admitted. Theorem union_powersets_subseteq : (forall A B,((subseteq (union (pow A) (pow B)) (pow (union A B))))). Admitted. Theorem powerset_emptyset : ((pow (emptyset)) = (cons (emptyset) (emptyset))). Admitted. Theorem powerset_union_subseteq : (forall A B,((subseteq (union (pow A) (pow B)) (pow (union A B))))). Admitted. Theorem subseteq_pow_unions : (forall A,((subseteq A (pow (unions A))))). Admitted. Theorem unions_pow : (forall A,(((unions (pow A)) = A))). Admitted. Theorem unions_elem_pow_iff : (forall A B,(((elem (unions A) (pow B))<->(elem A (pow (pow B)))))). Admitted. Theorem pow_inter : (forall A B,(((pow (inter A B)) = (inter (pow A) (pow B))))). Admitted. Theorem times_subseteq_left : (forall A C B,(((subseteq A C)->(subseteq (times A B) (times C B))))). Admitted. Theorem times_subseteq_right : (forall B D A,(((subseteq B D)->(subseteq (times A B) (times A D))))). Admitted. Theorem inter_times_intro : (forall w A B C D,(((elem w (times (inter A B) (inter C D)))->(elem w (inter (times A C) (times B D)))))). Admitted. Theorem inter_times_elim : (forall w A C B D,(((elem w (inter (times A C) (times B D)))->(elem w (times (inter A B) (inter C D)))))). Admitted. Theorem inter_times : (forall A B C D,(((times (inter A B) (inter C D)) = (inter (times A C) (times B D))))). Admitted. Theorem inter_times_right : (forall X Y Z,(((times (inter X Y) Z) = (inter (times X Z) (times Y Z))))). Admitted. Theorem inter_times_left : (forall X Y Z,(((times X (inter Y Z)) = (inter (times X Y) (times X Z))))). Admitted. Theorem union_times_intro : (forall w A B C D,(((elem w (times (union A B) (union C D)))->(elem w (union (union (union (times A C) (times B D)) (times A D)) (times B C)))))). Admitted. Theorem union_times_elim : (forall w A C B D,(((elem w (union (union (union (times A C) (times B D)) (times A D)) (times B C)))->(elem w (times (union A B) (union C D)))))). Admitted. Theorem union_times : (forall A B C D,(((times (union A B) (union C D)) = (union (union (union (times A C) (times B D)) (times A D)) (times B C))))). Admitted. Theorem union_times_left : (forall X Y Z,(((times (union X Y) Z) = (union (times X Z) (times Y Z))))). Admitted. Theorem union_times_right : (forall X Y Z,(((times X (union Y Z)) = (union (times X Y) (times X Z))))). Admitted. Definition elemminimal := fun x0 x1 : set => ((elem x0 x1)/\(notmeets x0 x1)). Theorem regularity_aux : (forall a A,(((elem a A)->(exists b,(((elem b A)/\(notmeets b A))))))). Admitted. Theorem regularity : (forall A,(((inhabited A)->(exists x1,((elemminimal x1 A)))))). Admitted. Theorem foundation : (forall A,(((A = (emptyset))\/(exists a,(((elem a A)/\(forall x,(((elem x a)->(notelem x A)))))))))). Admitted. Theorem in_irrefl : (forall A,(~((elem A A)))). Admitted. Theorem in_implies_neq : (forall a A,(((elem a A)->(a <> A)))). Admitted. Theorem in_asymmetric : (forall a b,(((elem a b)->(notelem b a)))). Admitted. Definition suc := fun x : set => (cons x x). Theorem suc_intro_self : (forall x,((elem x (suc x)))). Admitted. Theorem suc_intro_in : (forall x y,(((elem x y)->(elem x (suc y))))). Admitted. Theorem suc_elim : (forall x y,(((elem x (suc y))->((x = y)\/(elem x y))))). Admitted. Theorem suc_iff : (forall x y,(((elem x (suc y))<->((x = y)\/(elem x y))))). Admitted. Theorem suc_neq_emptyset : (forall x,(((suc x) <> (emptyset)))). Admitted. Theorem suc_subseteq_implies_in : (forall x y,(((subseteq (suc x) y)->(elem x y)))). Admitted. Theorem suc_neq_self : (forall x,(((suc x) <> x))). Admitted. Theorem suc_injective : (forall x y,((((suc x) = (suc y))->(x = y)))). Admitted. Theorem subseteq_self_suc_intro : (forall x,((subseteq x (suc x)))). Admitted. Theorem suc_subseteq_intro : (forall x y,((((elem x y)/\(subseteq x y))->(subseteq (suc x) y)))). Admitted. Theorem suc_subseteq_elim : (forall x y,(((subseteq (suc x) y)->((elem x y)/\(subseteq x y))))). Admitted. Theorem suc_next_subset : (forall x,(~((exists z,(((subset x z)/\(subset z (suc x)))))))). Admitted. Definition relation := fun R: set => (forall w,(((elem w R)->(exists x y,((w = (pair x y))))))). Definition comparable := fun a b R: set => ((elem (pair a b) R)\/(elem (pair b a) R)). Theorem relext : (forall R S,(((((relation R)/\(relation S))/\(forall x y,(((elem (pair x y) R)<->(elem (pair x y) S)))))->(R = S)))). Admitted. Definition family_of_relations := fun x0 : set => (forall x2,(((elem x2 x0)->(relation x2)))). Theorem unions_of_family_of_relations_is_relation : (forall F,(((family_of_relations F)->(relation (unions F))))). Admitted. Theorem inters_of_family_of_relations_is_relation : (forall F,(((family_of_relations F)->(relation (inters F))))). Admitted. Theorem union_relations_is_relation : (forall R S,((((relation R)/\(relation S))->(relation (union R S))))). Admitted. Theorem union_relations_is_relation_type : (forall R A B S C D,((((subseteq R (times A B))/\(subseteq S (times C D)))->(subseteq (union R S) (times (union A C) (union B D)))))). Admitted. Theorem inter_relations_is_relation : (forall R S,((((relation R)/\(relation S))->(relation (inter R S))))). Admitted. Theorem setminus_relations_is_relation : (forall R S,((((relation R)/\(relation S))->(relation (setminus R S))))). Admitted. Definition converse_relation := fun R : set => let MkReplFun := fun w : set => (Eps_i (fun z=>(exists x y,(((w = (pair x y))/\(z = (pair y x))))))) in {MkReplFun w|w :e (R)}. Theorem converse_intro : (forall y x R,(((elem (pair y x) R)->(elem (pair x y) (converse_relation R))))). Admitted. Theorem converse_elim : (forall x y R,(((elem (pair x y) (converse_relation R))->(elem (pair y x) R)))). Admitted. Theorem converse_iff : (forall x y R,(((elem (pair x y) (converse_relation R))<->(elem (pair y x) R)))). Admitted. Theorem converse_is_relation : (forall R,((relation (converse_relation R)))). Admitted. Theorem converse_converse_iff : (forall x y R,(((elem (pair x y) (converse_relation (converse_relation R)))<->(elem (pair x y) R)))). Admitted. Theorem converse_converse_eq : (forall R,(((relation R)->((converse_relation (converse_relation R)) = R)))). Admitted. Theorem converse_type : (forall R A B,(((subseteq R (times A B))->(subseteq (converse_relation R) (times B A))))). Admitted. Theorem converse_times : (forall B A,(((converse_relation (times B A)) = (times A B)))). Admitted. Theorem converse_emptyset : ((converse_relation (emptyset)) = (emptyset)). Admitted. Theorem converse_subseteq_intro : (forall R S,(((relation R)->((subseteq R S)->(subseteq (converse_relation R) (converse_relation S)))))). Admitted. Theorem converse_subseteq_elim : (forall R S,(((relation R)->((subseteq (converse_relation R) (converse_relation S))->(subseteq R S))))). Admitted. Theorem converse_subseteq_iff : (forall R S,(((relation R)->((subseteq (converse_relation R) (converse_relation S))<->(subseteq R S))))). Admitted. Theorem converse_union : (forall R S,(((converse_relation (union R S)) = (union (converse_relation R) (converse_relation S))))). Admitted. Theorem converse_inter : (forall R S,(((converse_relation (inter R S)) = (inter (converse_relation R) (converse_relation S))))). Admitted. Theorem converse_setminus : (forall R S,(((converse_relation (setminus R S)) = (setminus (converse_relation R) (converse_relation S))))). Admitted. Definition dom := fun R : set => let MkReplFun := fun w : set => (Eps_i (fun x=>(exists y,((w = (pair x y)))))) in {MkReplFun w|w :e (R)}. Theorem dom_iff : (forall a R,(((elem a (dom R))<->(exists b,((elem (pair a b) R)))))). Admitted. Theorem dom_intro : (forall a b R,(((elem (pair a b) R)->(elem a (dom R))))). Admitted. Theorem dom_emptyset : ((dom (emptyset)) = (emptyset)). Admitted. Theorem dom_times : (forall A B,((subseteq (dom (times A B)) A))). Admitted. Theorem dom_times_inhabited : (forall b B A,(((elem b B)->((dom (times A B)) = A)))). Admitted. Theorem dom_cons : (forall a b R,(((dom (cons (pair a b) R)) = (cons a (dom R))))). Admitted. Theorem dom_union : (forall A B,(((dom (union A B)) = (union (dom A) (dom B))))). Admitted. Theorem dom_inter : (forall A B,((subseteq (dom (inter A B)) (inter (dom A) (dom B))))). Admitted. Theorem dom_setminus : (forall A B,((supseteq (dom (setminus A B)) (setminus (dom A) (dom B))))). Admitted. Definition ran := fun R : set => let MkReplFun := fun w : set => (Eps_i (fun y=>(exists x,((w = (pair x y)))))) in {MkReplFun w|w :e (R)}. Theorem ran_iff : (forall b R,(((elem b (ran R))<->(exists a,((elem (pair a b) R)))))). Admitted. Theorem ran_intro : (forall a b R,(((elem (pair a b) R)->(elem b (ran R))))). Admitted. Theorem ran_emptyset : ((ran (emptyset)) = (emptyset)). Admitted. Theorem ran_times : (forall A B,((subseteq (ran (times A B)) B))). Admitted. Theorem ran_times_inhabited : (forall a A B,(((elem a A)->((ran (times A B)) = B)))). Admitted. Theorem ran_cons : (forall a b R,(((ran (cons (pair a b) R)) = (cons b (ran R))))). Admitted. Theorem ran_union : (forall A B,(((ran (union A B)) = (union (ran A) (ran B))))). Admitted. Theorem ran_inter : (forall A B,((subseteq (ran (inter A B)) (inter (ran A) (ran B))))). Admitted. Theorem ran_setminus : (forall A B,((supseteq (ran (setminus A B)) (setminus (ran A) (ran B))))). Admitted. Theorem dom_converse : (forall R,(((dom (converse_relation R)) = (ran R)))). Admitted. Theorem ran_converse : (forall R,(((ran (converse_relation R)) = (dom R)))). Admitted. Definition fld := fun R : set => (union (dom R) (ran R)). Theorem fld_iff : (forall c R,(((elem c (fld R))<->(exists d,(((elem (pair c d) R)\/(elem (pair d c) R))))))). Admitted. Theorem fld_intro_left : (forall a b R,(((elem (pair a b) R)->(elem a (fld R))))). Admitted. Theorem fld_intro_right : (forall a b R,(((elem (pair a b) R)->(elem b (fld R))))). Admitted. Theorem dom_subseteq_fld : (forall R,((subseteq (dom R) (fld R)))). Admitted. Theorem ran_subseteq_fld : (forall R,((subseteq (ran R) (fld R)))). Admitted. Theorem fld_times : (forall A B,((subseteq (fld (times A B)) (union A B)))). Admitted. Theorem relation_elem_times_fld : (forall R w,((((relation R)/\(elem w R))->(elem w (times (fld R) (fld R)))))). Admitted. Theorem relation_subseteq_times_fld : (forall R,(((relation R)->(subseteq R (times (fld R) (fld R)))))). Admitted. Theorem fld_universal : (forall A,(((fld (times A A)) = A))). Admitted. Theorem fld_emptyset : ((fld (emptyset)) = (emptyset)). Admitted. Theorem fld_cons : (forall a b R,(((fld (cons (pair a b) R)) = (cons a (cons b (fld R)))))). Admitted. Theorem fld_union : (forall A B,(((fld (union A B)) = (union (fld A) (fld B))))). Admitted. Theorem fld_inter : (forall A B,((subseteq (fld (inter A B)) (inter (fld A) (fld B))))). Admitted. Theorem fld_setminus : (forall A B,((supseteq (fld (setminus A B)) (setminus (fld A) (fld B))))). Admitted. Theorem fld_converse : (forall R,(((fld (converse_relation R)) = (fld R)))). Admitted. Definition img := fun R A : set => {b :e ((ran R))|(exists a,(((elem a A)/\(elem (pair a b) R))))}. Theorem img_elem_intro : (forall a A b R,((((elem a A)/\(elem (pair a b) R))->(elem b (img R A))))). Admitted. Theorem img_iff : (forall b R A,(((elem b (img R A))<->(exists a,(((elem a A)/\(elem (pair a b) R))))))). Admitted. Theorem img_subseteq : (forall A B R,(((subseteq A B)->(subseteq (img R A) (img R B))))). Admitted. Theorem img_subseteq_ran : (forall R A,((subseteq (img R A) (ran R)))). Admitted. Theorem img_dom : (forall R,(((img R (dom R)) = (ran R)))). Admitted. Theorem img_union : (forall R A B,(((img R (union A B)) = (union (img R A) (img R B))))). Admitted. Theorem img_inter : (forall R A B,((subseteq (img R (inter A B)) (inter (img R A) (img R B))))). Admitted. Theorem img_setminus : (forall R A B,((supseteq (img R (setminus A B)) (setminus (img R A) (img R B))))). Admitted. Theorem img_singleton_iff : (forall b R a,(((elem b (img R (cons a (emptyset))))<->(elem (pair a b) R)))). Admitted. Theorem img_singleton_intro : (forall b R a,(((elem b (img R (cons a (emptyset))))->((elem b (ran R))/\(elem (pair a b) R))))). Admitted. Theorem img_singleton : (forall R a,(((img R (cons a (emptyset))) = {b :e ((ran R))|(elem (pair a b) R)}))). Admitted. Theorem img_emptyset : (forall R,(((img R (emptyset)) = (emptyset)))). Admitted. Definition preimg := fun R B : set => {a :e ((dom R))|(exists b,(((elem b B)/\(elem (pair a b) R))))}. Theorem preimg_iff : (forall a R B,(((elem a (preimg R B))<->(exists b,(((elem b B)/\(elem (pair a b) R))))))). Admitted. Theorem preim_eq_img_of_converse : (forall R B,(((preimg R B) = (img (converse_relation R) B)))). Admitted. Theorem preimg_subseteq : (forall A B R,(((subseteq A B)->(subseteq (preimg R A) (preimg R B))))). Admitted. Theorem preimg_subseteq_dom : (forall R A,((subseteq (preimg R A) (dom R)))). Admitted. Theorem preimg_union : (forall R A B,(((preimg R (union A B)) = (union (preimg R A) (preimg R B))))). Admitted. Theorem preimg_inter : (forall R A B,((subseteq (preimg R (inter A B)) (inter (preimg R A) (preimg R B))))). Admitted. Theorem preimg_setminus : (forall R A B,((supseteq (preimg R (setminus A B)) (setminus (preimg R A) (preimg R B))))). Admitted. Definition upward_closure := fun R a : set => {b :e ((ran R))|(elem (pair a b) R)}. Definition downward_closure := fun R b : set => {a :e ((dom R))|(elem (pair a b) R)}. Theorem downward_closure_iff : (forall a R b,(((elem a (downward_closure R b))<->(elem (pair a b) R)))). Admitted. Definition circ := fun S R : set => ReplSep2 ((dom R))(fun dummyVar => (ran S))(fun x z => (exists y,(((elem (pair x y) R)/\(elem (pair y z) S)))))(fun x z => (pair x z)). Theorem circ_is_relation : (forall S R,((relation (circ S R)))). Admitted. Theorem circ_elem_intro : (forall x y R z S,((((elem (pair x y) R)/\(elem (pair y z) S))->(elem (pair x z) (circ S R))))). Admitted. Theorem circ_elem_elim : (forall x z S R,(((elem (pair x z) (circ S R))->(exists y,(((elem (pair x y) R)/\(elem (pair y z) S))))))). Admitted. Theorem circ_iff : (forall x z S R,(((elem (pair x z) (circ S R))<->(exists y,(((elem (pair x y) R)/\(elem (pair y z) S))))))). Admitted. Theorem circ_assoc : (forall T S R,(((circ (circ T S) R) = (circ T (circ S R))))). Admitted. Theorem circ_converse_intro_tuple : (forall a c R S,(((elem (pair a c) (circ (converse_relation R) (converse_relation S)))->(elem (pair a c) (converse_relation (circ S R)))))). Admitted. Theorem circ_converse_elim : (forall a c S R,(((elem (pair a c) (converse_relation (circ S R)))->(elem (pair a c) (circ (converse_relation R) (converse_relation S)))))). Admitted. Theorem circ_converse : (forall S R,(((converse_relation (circ S R)) = (circ (converse_relation R) (converse_relation S))))). Admitted. Definition restrl := fun R X : set => {w :e (R)|(exists x y,(((elem x X)/\(w = (pair x y)))))}. Theorem restrl_iff : (forall a b R X,(((elem (pair a b) (restrl R X))<->((elem (pair a b) R)/\(elem a X))))). Admitted. Theorem restrl_subseteq : (forall R X,((subseteq (restrl R X) R))). Admitted. Theorem elem_dom_of_restrl_implies_elem_dom_and_restr : (forall x R X,(((elem x (dom (restrl R X)))->((elem x (dom R))/\(elem x X))))). Admitted. Theorem elem_dom_and_restr_implies_elem_of_restr : (forall x R X,((((elem x (dom R))/\(elem x X))->(elem x (dom (restrl R X)))))). Admitted. Theorem restrl_eq_inter : (forall R X,(((relation R)->((restrl R X) = (inter R (times X (ran R))))))). Admitted. Theorem dom_of_restrl_eq_inter : (forall R X,(((relation R)->((dom (restrl R X)) = (inter (dom R) X))))). Admitted. Theorem restrl_restrl : (forall V U R,(((subseteq V U)->((restrl (restrl R U) V) = (restrl R V))))). Admitted. Theorem restrl_by_dom : (forall R,(((relation R)->((restrl R (dom R)) = R)))). Admitted. Theorem restrl_dom : (forall R X,((subseteq (dom (restrl R X)) X))). Admitted. Theorem restrl_ran_elim : (forall X R b,((((subseteq X (dom R))/\(elem b (ran (restrl R X))))->(elem b (img R X))))). Admitted. Theorem restrl_ran_intro : (forall X R b,((((subseteq X (dom R))/\(elem b (img R X)))->(elem b (ran (restrl R X)))))). Admitted. Theorem restrl_ran : (forall X R,(((subseteq X (dom R))->((ran (restrl R X)) = (img R X))))). Admitted. Theorem restrl_img : (forall X R A,(((subseteq X (dom R))->((img (restrl R X) A) = (img R (inter X A)))))). Admitted. Definition binary_relation_on := fun x0 x1 : set => (subseteq x0 (times x1 x1)). Theorem relation_subseteq_intro_elem : (forall R B A w,((((((relation R)/\(subseteq (ran R) B))/\(subseteq (dom R) A))/\(elem w R))->(elem w (times A B))))). Admitted. Theorem relation_subseteq_intro : (forall R B A,(((((relation R)/\(subseteq (ran R) B))/\(subseteq (dom R) A))->(subseteq R (times A B))))). Admitted. Theorem relation_subseteq_implies_dom_subseteq_elem : (forall R A B a,((((subseteq R (times A B))/\(elem a (dom R)))->(elem a A)))). Admitted. Theorem relation_subseteq_implies_dom_subseteq : (forall R A B,(((subseteq R (times A B))->(subseteq (dom R) A)))). Admitted. Theorem relation_subseteq_implies_ran_subseteq_elem : (forall R A B b,((((subseteq R (times A B))/\(elem b (ran R)))->(elem b B)))). Admitted. Theorem relation_subseteq_implies_ran_subseteq : (forall R A B,(((subseteq R (times A B))->(subseteq (ran R) B)))). Admitted. Definition rels := fun A B : set => (pow (times A B)). Theorem rels_intro : (forall R A B,(((subseteq R (times A B))->(elem R (rels A B))))). Admitted. Theorem rels_intro_dom_and_ran : (forall R A B,(((((relation R)/\(subseteq (dom R) A))/\(subseteq (ran R) B))->(elem R (rels A B))))). Admitted. Theorem rels_elim : (forall R A B,(((elem R (rels A B))->(subseteq R (times A B))))). Admitted. Theorem rels_weaken_dom : (forall R A B C,((((elem R (rels A B))/\(subseteq A C))->(elem R (rels C B))))). Admitted. Theorem rels_weaken_codom : (forall R A B D,((((elem R (rels A B))/\(subseteq B D))->(elem R (rels A D))))). Admitted. Definition id := fun A : set => ReplSep (A)(fun a => True)(fun a => (pair a a)). Theorem id_iff : (forall a b A,(((elem (pair a b) (id A))<->((a = b)/\(elem b A))))). Admitted. Theorem id_elem_intro : (forall a A,(((elem a A)->(elem (pair a a) (id A))))). Admitted. Theorem id_elem_inspect : (forall w A,(((elem w (id A))->(exists a,(((elem a A)/\(w = (pair a a)))))))). Admitted. Theorem id_is_relation : (forall A,((relation (id A)))). Admitted. Theorem id_dom : (forall A,(((dom (id A)) = A))). Admitted. Theorem id_ran : (forall A,(((ran (id A)) = A))). Admitted. Theorem id_img : (forall A B,(((img (id A) B) = (inter A B)))). Admitted. Theorem id_elem_rels : (forall A,((elem (id A) (rels A A)))). Admitted. Definition memrel := fun A : set => ReplSep2 (A)(fun dummyVar => A)(fun a b => (elem a b))(fun a b => (pair a b)). Theorem memrel_elem_intro : (forall a A b,(((((elem a A)/\(elem b A))/\(elem a b))->(elem (pair a b) (memrel A))))). Admitted. Theorem memrel_elem_inspect : (forall w A,(((elem w (memrel A))->(exists a b,((((elem a A)/\(elem b A))/\((w = (pair a b))/\(elem a b)))))))). Admitted. Theorem memrel_is_relation : (forall A,((relation (memrel A)))). Admitted. Definition subseteqrel := fun A : set => ReplSep2 (A)(fun dummyVar => A)(fun a b => (subseteq a b))(fun a b => (pair a b)). Theorem subseteqrel_is_relation : (forall A,((relation (subseteqrel A)))). Admitted. Definition injective := fun R: set => (forall a b aprime,((((elem (pair a b) R)/\(elem (pair aprime b) R))->(a = aprime)))). Definition leftunique := fun x0 : set => (injective x0). Theorem subseteq_of_injective_is_injective : (forall S R,((((subseteq S R)/\(injective R))->(injective S)))). Admitted. Theorem restrl_injective : (forall R A,(((injective R)->(injective (restrl R A))))). Admitted. Theorem circ_injective : (forall R S,((((injective R)/\(injective S))->(injective (circ S R))))). Admitted. Theorem identity_injective : (forall A,((injective (id A)))). Admitted. Definition rightunique := fun R: set => (forall a b bprime,((((elem (pair a b) R)/\(elem (pair a bprime) R))->(b = bprime)))). Definition onetoone := fun x0 : set => ((rightunique x0)/\(injective x0)). Theorem subseteq_of_rightunique_is_rightunique : (forall S R,((((subseteq S R)/\(rightunique R))->(rightunique S)))). Admitted. Theorem circ_rightunique : (forall R S,((((rightunique R)/\(rightunique S))->(rightunique (circ S R))))). Admitted. Definition lefttotal := fun R A: set => (forall a,(((elem a A)->(exists b,((elem (pair a b) R)))))). Definition righttotal := fun R B: set => (forall b,(((elem b B)->(exists a,((elem (pair a b) R)))))). Definition surjective := fun x0 x1 : set => (righttotal x0 x1). Definition inductive_set := fun x0 : set => ((elem (emptyset) x0)/\(forall a,(((elem a x0)->(elem (suc a) x0))))). Definition transitiveset := fun A: set => (forall x y,((((elem x y)/\(elem y A))->(elem x A)))). Theorem transitiveset_iff_subseteq : (forall A,(((transitiveset A)<->(forall a,(((elem a A)->(subseteq a A))))))). Admitted. Theorem transitiveset_iff_pow : (forall A,(((transitiveset A)<->(subseteq A (pow A))))). Admitted. Theorem transitiveset_iff_unions_suc : (forall A,(((transitiveset A)<->((unions (suc A)) = A)))). Admitted. Theorem transitiveset_iff_unions_subseteq : (forall A,(((transitiveset A)<->(subseteq (unions A) A)))). Admitted. Theorem transitiveset_upair : (forall A a b,((((transitiveset A)/\(elem (cons a (cons b (emptyset))) A))->((elem a A)/\(elem b A))))). Admitted. Theorem emptyset_transitiveset : (transitiveset (emptyset)). Admitted. Theorem union_of_transitiveset_is_transitiveset : (forall A B,((((transitiveset A)/\(transitiveset B))->(transitiveset (union A B))))). Admitted. Theorem inter_of_transitiveset_is_transitiveset : (forall A B,((((transitiveset A)/\(transitiveset B))->(transitiveset (inter A B))))). Admitted. Theorem suc_of_transitiveset_is_transitiveset : (forall A,(((transitiveset A)->(transitiveset (suc A))))). Admitted. Theorem unions_of_transitiveset_is_transitiveset : (forall A,(((transitiveset A)->(transitiveset (unions A))))). Admitted. Theorem unions_family_of_transitiveset_is_transitiveset : (forall A,(((forall x3,(((elem x3 A)->(transitiveset x3))))->(transitiveset (unions A))))). Admitted. Theorem inters_family_of_transitiveset_is_transitiveset : (forall A,(((forall x4,(((elem x4 A)->(transitiveset x4))))->(transitiveset (inters A))))). Admitted. Definition ordinal := fun alpha: set => ((transitiveset alpha)/\(forall x5,(((elem x5 alpha)->(transitiveset x5))))). Theorem ordinal_intro : (forall alpha,((((transitiveset alpha)/\(forall x6,(((elem x6 alpha)->(transitiveset x6)))))->(ordinal alpha)))). Admitted. Theorem ordinal_is_transitiveset : (forall alpha,(((ordinal alpha)->(transitiveset alpha)))). Admitted. Theorem ordinal_elem_is_transitiveset : (forall alpha A,((((ordinal alpha)/\(elem A alpha))->(transitiveset A)))). Admitted. Theorem elem_of_ordinal_is_ordinal : (forall alpha beta,((((ordinal alpha)/\(elem beta alpha))->(ordinal beta)))). Admitted. Theorem suc_ordinal_implies_ordinal : (forall alpha,(((ordinal (suc alpha))->(ordinal alpha)))). Admitted. Theorem transitivesubseteq_of_ordinal_is_ordinal : (forall alpha beta,(((((ordinal alpha)/\(subseteq beta alpha))/\(transitiveset beta))->(ordinal beta)))). Admitted. Theorem ordinal_elem_implies_subseteq : (forall alpha beta,(((((ordinal alpha)/\(ordinal beta))/\(elem alpha beta))->(subseteq alpha beta)))). Admitted. Theorem ordinal_transitivity : (forall alpha gamma beta,((((ordinal alpha)/\((elem gamma beta)/\(elem beta alpha)))->(elem gamma alpha)))). Admitted. Theorem ordinal_suc_subseteq : (forall beta alpha,((((ordinal beta)/\(elem alpha beta))->(subseteq (suc alpha) beta)))). Admitted. Definition ordinal_prec := fun x0 x1 : set => ((ordinal x1)/\(elem x0 x1)). Definition ordinal_preceq := fun x0 x1 : set => ((ordinal x1)/\(subseteq x0 x1)). Theorem prec_is_ordinal : (forall alpha beta,(((ordinal_prec alpha beta)->(ordinal alpha)))). Admitted. Theorem ordinal_elem_connex : (forall alpha beta,((((ordinal alpha)/\(ordinal beta))->(((elem alpha beta)\/(elem beta alpha))\/(alpha = beta))))). Admitted. Theorem ordinal_proper_subset_implies_elem : (forall alpha beta,(((((ordinal alpha)/\(ordinal beta))/\(subset alpha beta))->(elem alpha beta)))). Admitted. Theorem ordinal_elem_implies_proper_subset : (forall alpha beta,(((((ordinal alpha)/\(ordinal beta))/\(elem alpha beta))->(subset alpha beta)))). Admitted. Theorem ordinal_preceq_implies_subseteq : (forall alpha beta,(((((ordinal alpha)/\(ordinal beta))/\(ordinal_preceq alpha beta))->(subseteq alpha beta)))). Admitted. Theorem ordinal_elem_or_subseteq : (forall alpha beta,((((ordinal alpha)/\(ordinal beta))->((elem alpha beta)\/(subseteq beta alpha))))). Admitted. Theorem ordinal_subseteq_or_subseteq : (forall alpha beta,((((ordinal alpha)/\(ordinal beta))->((subseteq alpha beta)\/(subseteq beta alpha))))). Admitted. Theorem ordinal_subseteq_implies_elem_or_eq : (forall alpha beta,(((((ordinal alpha)/\(ordinal beta))/\(subseteq alpha beta))->((elem alpha beta)\/(alpha = beta))))). Admitted. Theorem ordinal_subset_trichotomy : (forall alpha beta,((((ordinal alpha)/\(ordinal beta))->(((subset alpha beta)\/(subset beta alpha))\/(alpha = beta))))). Admitted. Theorem ordinal_nor_elem_implies_eq : (forall alpha beta,(((((ordinal alpha)/\(ordinal beta))/\(nor(elem alpha beta) (elem beta alpha)))->(alpha = beta)))). Admitted. Theorem ordinal_in_trichotomy : (forall alpha beta,((((ordinal alpha)/\(ordinal beta))->(((elem alpha beta)\/(elem beta alpha))\/(alpha = beta))))). Admitted. Theorem ordinal_prec_trichotomy : (forall alpha beta,(((((ordinal alpha)/\(ordinal beta))/\(nor(ordinal_prec alpha beta) (ordinal_prec beta alpha)))->(alpha = beta)))). Admitted. Theorem ordinal_elem_or_superset : (forall alpha beta,((((ordinal alpha)/\(ordinal beta))->((elem alpha beta)\/(subseteq beta alpha))))). Admitted. Theorem emptyset_is_ordinal : (ordinal (emptyset)). Admitted. Theorem suc_ordinal : (forall alpha,(((ordinal alpha)->(ordinal (suc alpha))))). Admitted. Theorem ordinal_iff_suc_ordinal : (forall alpha,(((ordinal alpha)<->(ordinal (suc alpha))))). Admitted. Theorem ordinal_in_suc : (forall alpha,(((ordinal alpha)->(elem alpha (suc alpha))))). Admitted. Theorem ordinal_precedes_suc : (forall alpha,(((ordinal alpha)->(ordinal_prec alpha (suc alpha))))). Admitted. Theorem ordinal_elem_implies_subset_of_suc : (forall alpha beta,(((((ordinal alpha)/\(ordinal beta))/\(elem alpha beta))->(subseteq alpha (suc beta))))). Admitted. Theorem unions_of_ordinal_is_ordinal : (forall alpha,(((ordinal alpha)->(ordinal (unions alpha))))). Admitted. Theorem ordinal_subseteq_unions : (forall alpha,(((ordinal alpha)->(subseteq (unions alpha) alpha)))). Admitted. Theorem union_of_two_ordinals_is_ordinal : (forall alpha beta,((((ordinal alpha)/\(ordinal beta))->(ordinal (union alpha beta))))). Admitted. Theorem ordinal_empty_or_emptyset_elem : (forall alpha,(((ordinal alpha)->((alpha = (emptyset))\/(elem (emptyset) alpha))))). Admitted. Theorem transitive_set_of_ordinals_is_ordinal : (forall A,((((forall alpha,(((elem alpha A)->(ordinal alpha))))/\(transitiveset A))->(ordinal A)))). Admitted. Theorem buraliforti_antinomy : ~((exists Omega,((forall alpha,(((elem alpha Omega)<->(ordinal alpha))))))). Admitted. Theorem inters_of_ordinals_is_ordinal : (forall A,((((inhabited A)/\(forall alpha,(((elem alpha A)->(ordinal alpha)))))->(ordinal (inters A))))). Admitted. Theorem inters_of_ordinals_subseteq : (forall A,((((inhabited A)/\(forall alpha,(((elem alpha A)->(ordinal alpha)))))->(forall alpha,(((elem alpha A)->(subseteq (inters A) alpha))))))). Admitted. Theorem inters_of_ordinals_elem : (forall A,((((inhabited A)/\(forall alpha,(((elem alpha A)->(ordinal alpha)))))->(elem (inters A) A)))). Admitted. Theorem inters_of_ordinals_is_minimal : (forall A,((((inhabited A)/\(forall alpha,(((elem alpha A)->(ordinal alpha)))))->(elemminimal (inters A) A)))). Admitted. Theorem inters_of_ordinals_is_minimal_alternate : (forall A,((((inhabited A)/\(forall alpha,(((elem alpha A)->(ordinal alpha)))))->(forall alpha,(((elem alpha A)->(((inters A) = alpha)\/(elem (inters A) alpha)))))))). Admitted. Theorem inter_of_two_ordinals_is_ordinal : (forall alpha beta,((((ordinal alpha)/\(ordinal beta))->(ordinal (inter alpha beta))))). Admitted. Definition limit_ordinal := fun lambda: set => ((ordinal_prec (emptyset) lambda)/\(forall alpha,(((elem alpha lambda)->(elem (suc alpha) lambda))))). Definition successor_ordinal := fun alpha: set => (exists beta,(((ordinal beta)/\(alpha = (suc beta))))). Theorem positive_ordinal_is_limit_or_successor : (forall alpha,((((ordinal_prec (emptyset) alpha)/\(ordinal alpha))->((limit_ordinal alpha)\/(successor_ordinal alpha))))). Admitted. Theorem zero_not_successorordinal : ~((successor_ordinal (emptyset))). Admitted. Theorem zero_not_limitordinal : ~((limit_ordinal (emptyset))). Admitted. Theorem suc_elem_limitordinal : (forall lambda alpha,((((limit_ordinal lambda)/\(elem alpha lambda))->(elem (suc alpha) lambda)))). Admitted. Theorem limitordinal_eq_unions : (forall lambda,(((limit_ordinal lambda)->((unions lambda) = lambda)))). Admitted. Definition function := fun x0 : set => ((rightunique x0)/\(relation x0)). Definition appl := fun f x : set => (unions (img f (cons x (emptyset)))). Theorem function_rightunique : (forall f a b bprime,((((function f)/\((elem (pair a b) f)/\(elem (pair a bprime) f)))->(b = bprime)))). Admitted. Theorem function_appl_intro : (forall f a b,((((function f)/\(elem (pair a b) f))->((appl f a) = b)))). Admitted. Theorem function_member_elim : (forall f w,((((function f)/\(elem w f))->(exists x,(((elem x (dom f))/\(w = (pair x (appl f x))))))))). Admitted. Theorem function_appl_elim : (forall f x,((((function f)/\(elem x (dom f)))->(elem (pair x (appl f x)) f)))). Admitted. Theorem function_appl_iff : (forall f a b,(((function f)->((elem (pair a b) f)<->((elem a (dom f))/\((appl f a) = b)))))). Admitted. Theorem fun_subseteq : (forall f g,((((((function f)/\(function g))/\(subseteq (dom f) (dom g)))/\(forall x,(((elem x (dom f))->((appl f x) = (appl g x))))))->(subseteq f g)))). Admitted. Theorem funext : (forall f g,((((((function f)/\(function g))/\((dom f) = (dom g)))/\(forall x,(((appl f x) = (appl g x)))))->(f = g)))). Admitted. Definition function_on := fun x0 x1 : set => ((function x0)/\(x1 = (dom x0))). Definition function_to := fun x0 x1 : set => ((function x0)/\(forall x,(((elem x (dom x0))->(elem (appl x0 x) x1))))). Definition function_from_to := fun x0 x1 x2 : set => ((function_to x0 x2)/\((dom x0) = x1)). Theorem function_on_weaken_codom : (forall f B C,((((function_to f B)/\(subseteq B C))->(function_to f C)))). Admitted. Theorem function_to_ran : (forall f B,(((function_to f B)->(subseteq (ran f) B)))). Admitted. Theorem function_from_to_weaken_codom : (forall f A B C,((((function_from_to f A B)/\(subseteq B C))->(function_from_to f A C)))). Admitted. Definition funs := fun A B : set => {f :e ((rels A B))|((subseteq A (dom f))/\(rightunique f))}. Theorem funs_subseteq_rels : (forall A B,((subseteq (funs A B) (rels A B)))). Admitted. Theorem funs_intro : (forall f A B,(((function_from_to f A B)->(elem f (funs A B))))). Admitted. Theorem funs_weaken_codom : (forall f A B D,((((elem f (funs A B))/\(subseteq B D))->(elem f (funs A D))))). Admitted. Theorem img_of_function_intro : (forall f x X,((((function f)/\(elem x (inter (dom f) X)))->(elem (appl f x) (img f X))))). Admitted. Theorem img_of_function_elim : (forall f y X,((((function f)/\(elem y (img f X)))->(exists x,(((elem x (inter (dom f) X))/\(y = (appl f x)))))))). Admitted. Theorem img_of_function : (forall f X,(((function f)->((img f X) = ReplSep ((inter (dom f) X))(fun x => True)(fun x => (appl f x)))))). Admitted. Definition family_of_functions := fun x0 : set => (forall x11,(((elem x11 x0)->(function x11)))). Theorem unions_of_compatible_family_of_function_is_function : (forall F,((((family_of_functions F)/\(forall f g,((((elem f F)/\(elem g F))->((subseteq f g)\/(subseteq g f))))))->(function (unions F))))). Admitted. Theorem emptyset_is_function : (function (emptyset)). Admitted. Theorem emptyset_is_function_on_emptyset : (function_on (emptyset) (emptyset)). Admitted. Theorem codom_of_emptyset_can_be_anything : (forall X,((function_to (emptyset) X))). Admitted. Theorem emptyset_is_injective : (injective (emptyset)). Admitted. Definition composable := fun x0 x1 : set => (subseteq (ran x1) (dom x0)). Theorem function_circ : (forall f g,((((rightunique f)/\(rightunique g))->(function (circ g f))))). Admitted. Theorem circ_appl : (forall f g x,((((((function f)/\(function g))/\(composable g f))/\(elem x (dom f)))->((appl (circ g f) x) = (appl g (appl f x)))))). Admitted. Theorem dom_of_circ : (forall f g,(((((function f)/\(function g))/\(composable g f))->((dom (circ g f)) = (preimg f (dom g)))))). Admitted. Theorem dom_circ_exact : (forall f g,(((((function f)/\(function g))/\((ran f) = (dom g)))->((dom (circ g f)) = (dom f))))). Admitted. Theorem ran_of_circ_intro : (forall f g y,((((((function f)/\(function g))/\(composable g f))/\(elem y (img g (ran f))))->(elem y (ran (circ g f)))))). Admitted. Theorem ran_of_circ_elim : (forall f g y,((((((function f)/\(function g))/\(composable g f))/\(elem y (ran (circ g f))))->(elem y (img g (ran f)))))). Admitted. Theorem ran_of_circ : (forall f g,(((((function f)/\(function g))/\(composable g f))->((ran (circ g f)) = (img g (ran f)))))). Admitted. Theorem ran_circ_exact : (forall f g,(((((function f)/\(function g))/\((ran f) = (dom g)))->((ran (circ g f)) = (ran g))))). Admitted. Theorem img_of_circ_elim : (forall f g c A,((((((function f)/\(function g))/\(subseteq (ran f) (dom g)))/\(elem c (img (circ g f) A)))->(elem c (img g (img f A)))))). Admitted. Theorem img_of_circ : (forall f g A,(((((function f)/\(function g))/\(subseteq (ran f) (dom g)))->((img (circ g f) A) = (img g (img f A)))))). Admitted. Theorem restrl_of_function_is_function : (forall f A,(((function f)->(function (restrl f A))))). Admitted. Theorem restrl_of_function_appl : (forall f A a,(((((function f)/\(subseteq A (dom f)))/\(elem a A))->((appl (restrl f A) a) = (appl f a))))). Admitted. Theorem function_appl_default : (forall x f,(((notelem x (dom f))->((appl f x) = (emptyset))))). Admitted. Theorem injective_function : (forall f,(((function f)->((injective f)<->(forall x y,((((elem x (dom f))/\(elem y (dom f)))->(((appl f x) = (appl f y))->(x = y))))))))). Admitted. Definition injection := fun x0 : set => ((function x0)/\(injective x0)). Definition surjects := fun f Y: set => (Y = ReplSep ((dom f))(fun x => True)(fun x => (appl f x))). Theorem surjects_img : (forall f,((surjects f (img f (dom f))))). Admitted. Theorem surjects_implies_img : (forall f Y,(((surjects f Y)->(Y = (img f (dom f)))))). Admitted. Theorem surjects_implies_ran_eq : (forall f Y,((((function f)/\(surjects f Y))->((ran f) = Y)))). Admitted. Theorem ran_eq_implies_surjects : (forall f Y,((((function f)/\((ran f) = Y))->(surjects f Y)))). Admitted. Theorem surjects_iff_ran_eq : (forall f Y,(((function f)->((surjects f Y)<->((ran f) = Y))))). Admitted. Definition bijection := fun f X Y: set => (((dom f) = X)/\((surjects f Y)/\(injection f))). Theorem bijection_circ : (forall f A B g C,((((bijection f A B)/\(bijection g B C))->(bijection (circ g f) A C)))). Admitted. Theorem converse_of_function_is_injective : (forall f,(((function f)->(injective (converse_relation f))))). Admitted. Theorem injective_converse_is_function : (forall f,(((injective f)->(function (converse_relation f))))). Admitted. Theorem bijective_converse_is_function : (forall f A B,(((bijection f A B)->(function (converse_relation f))))). Admitted. Theorem bijection_converse_is_bijection : (forall f A B,(((bijection f A B)->(bijection (converse_relation f) B A)))). Admitted. Definition leftinverse := fun x0 x1 : set => (forall x,(((elem x (dom x1))->((appl x0 (appl x1 x)) = x)))). Definition rightinverse := fun x0 x1 : set => ((circ x1 x0) = (id (dom x0))). Definition rightinverseon := fun x0 x1 x2 : set => ((circ x1 x0) = (id x2)). Theorem injective_converse_is_leftinverse : (forall f,(((injection f)->(leftinverse (converse_relation f) f)))). Admitted. Theorem id_rightunique : (forall A,((rightunique (id A)))). Admitted. Theorem id_is_function : (forall A,((function (id A)))). Admitted. Theorem id_is_function_on : (forall A,((function_on (id A) A))). Admitted. Theorem id_is_function_to : (forall A,((function_to (id A) A))). Admitted. Theorem id_is_function_to_form : (forall A,((function_from_to (id A) A A))). Admitted. Theorem id_elem_funs : (forall A,((elem (id A) (funs A A)))). Admitted. Theorem id_appl : (forall a A f,((((elem a A)/\(f = (id A)))->((appl f a) = a)))). Admitted. Theorem id_is_bijection : (forall A,((bijection (id A) A A))). Admitted.