Primitive. The name Eps_i is a term of type (setprop)set.
Axiom. (Eps_i_ax) We take the following as an axiom:
∀P : setprop, ∀x : set, P xP (Eps_i P)
Definition. We define True to be ∀p : prop, pp of type prop.
Definition. We define False to be ∀p : prop, p of type prop.
Definition. We define not to be λA : propAFalse of type propprop.
Notation. We use ¬ as a prefix operator with priority 700 corresponding to applying term not.
Definition. We define and to be λA B : prop∀p : prop, (ABp)p of type proppropprop.
Notation. We use as an infix operator with priority 780 and which associates to the left corresponding to applying term and.
Definition. We define or to be λA B : prop∀p : prop, (Ap)(Bp)p of type proppropprop.
Notation. We use as an infix operator with priority 785 and which associates to the left corresponding to applying term or.
Definition. We define iff to be λA B : propand (AB) (BA) of type proppropprop.
Notation. We use as an infix operator with priority 805 and no associativity corresponding to applying term iff.
Beginning of Section Eq
Variable A : SType
Definition. We define eq to be λx y : A∀Q : AAprop, Q x yQ y x of type AAprop.
Definition. We define neq to be λx y : A¬ eq x y of type AAprop.
End of Section Eq
Notation. We use = as an infix operator with priority 502 and no associativity corresponding to applying term eq.
Notation. We use as an infix operator with priority 502 and no associativity corresponding to applying term neq.
Beginning of Section FE
Variable A B : SType
Axiom. (func_ext) We take the following as an axiom:
∀f g : AB, (∀x : A, f x = g x)f = g
End of Section FE
Beginning of Section Ex
Variable A : SType
Definition. We define ex to be λQ : Aprop∀P : prop, (∀x : A, Q xP)P of type (Aprop)prop.
End of Section Ex
Notation. We use x...y [possibly with ascriptions] , B as a binder notation corresponding to a term constructed using ex.
Axiom. (prop_ext) We take the following as an axiom:
∀p q : prop, iff p qp = q
Primitive. The name In is a term of type setsetprop.
Notation. We use as an infix operator with priority 500 and no associativity corresponding to applying term In. Furthermore, we may write xA, B to mean x : set, xAB.
Definition. We define Subq to be λA B ⇒ ∀xA, x B of type setsetprop.
Notation. We use as an infix operator with priority 500 and no associativity corresponding to applying term Subq. Furthermore, we may write xA, B to mean x : set, xAB.
Axiom. (set_ext) We take the following as an axiom:
∀X Y : set, X YY XX = Y
Axiom. (In_ind) We take the following as an axiom:
∀P : setprop, (∀X : set, (∀xX, P x)P X)∀X : set, P X
Notation. We use x...y [possibly with ascriptions] , B as a binder notation corresponding to a term constructed using ex and handling ∈ or ⊆ ascriptions using and.
Primitive. The name Empty is a term of type set.
Axiom. (EmptyAx) We take the following as an axiom:
¬ ∃x : set, x Empty
Primitive. The name is a term of type setset.
Axiom. (UnionEq) We take the following as an axiom:
∀X x, x X ∃Y, x Y Y X
Primitive. The name 𝒫 is a term of type setset.
Axiom. (PowerEq) We take the following as an axiom:
∀X Y : set, Y 𝒫 X Y X
Primitive. The name Repl is a term of type set(setset)set.
Notation. {B| xA} is notation for Repl Ax . B).
Axiom. (ReplEq) We take the following as an axiom:
∀A : set, ∀F : setset, ∀y : set, y {F x|xA} ∃xA, y = F x
Definition. We define TransSet to be λU : set∀xU, x U of type setprop.
Definition. We define Union_closed to be λU : set∀X : set, X U X U of type setprop.
Definition. We define Power_closed to be λU : set∀X : set, X U𝒫 X U of type setprop.
Definition. We define Repl_closed to be λU : set∀X : set, X U∀F : setset, (∀x : set, x XF x U){F x|xX} U of type setprop.
Definition. We define ZF_closed to be λU : setUnion_closed U Power_closed U Repl_closed U of type setprop.
Primitive. The name UnivOf is a term of type setset.
Axiom. (UnivOf_In) We take the following as an axiom:
∀N : set, N UnivOf N
Axiom. (UnivOf_TransSet) We take the following as an axiom:
∀N : set, TransSet (UnivOf N)
Axiom. (UnivOf_ZF_closed) We take the following as an axiom:
∀N : set, ZF_closed (UnivOf N)
Axiom. (UnivOf_Min) We take the following as an axiom:
∀N U : set, N UTransSet UZF_closed UUnivOf N U
Axiom. (FalseE) We take the following as an axiom:
False∀p : prop, p
Axiom. (TrueI) We take the following as an axiom:
True
Axiom. (andI) We take the following as an axiom:
∀A B : prop, ABA B
Axiom. (andEL) We take the following as an axiom:
∀A B : prop, A BA
Axiom. (andER) We take the following as an axiom:
∀A B : prop, A BB
Axiom. (orIL) We take the following as an axiom:
∀A B : prop, AA B
Axiom. (orIR) We take the following as an axiom:
∀A B : prop, BA B
Beginning of Section PropN
Variable P1 P2 P3 : prop
Axiom. (and3I) We take the following as an axiom:
P1P2P3P1 P2 P3
Axiom. (and3E) We take the following as an axiom:
P1 P2 P3(∀p : prop, (P1P2P3p)p)
Axiom. (or3I1) We take the following as an axiom:
P1P1 P2 P3
Axiom. (or3I2) We take the following as an axiom:
P2P1 P2 P3
Axiom. (or3I3) We take the following as an axiom:
P3P1 P2 P3
Axiom. (or3E) We take the following as an axiom:
P1 P2 P3(∀p : prop, (P1p)(P2p)(P3p)p)
Variable P4 : prop
Axiom. (and4I) We take the following as an axiom:
P1P2P3P4P1 P2 P3 P4
Variable P5 : prop
Axiom. (and5I) We take the following as an axiom:
P1P2P3P4P5P1 P2 P3 P4 P5
End of Section PropN
Axiom. (not_or_and_demorgan) We take the following as an axiom:
∀A B : prop, ¬ (A B)¬ A ¬ B
Axiom. (not_ex_all_demorgan_i) We take the following as an axiom:
∀P : setprop, (¬ ∃x, P x)∀x, ¬ P x
Axiom. (iffI) We take the following as an axiom:
∀A B : prop, (AB)(BA)(A B)
Axiom. (iffEL) We take the following as an axiom:
∀A B : prop, (A B)AB
Axiom. (iffER) We take the following as an axiom:
∀A B : prop, (A B)BA
Axiom. (iff_refl) We take the following as an axiom:
∀A : prop, A A
Axiom. (iff_sym) We take the following as an axiom:
∀A B : prop, (A B)(B A)
Axiom. (iff_trans) We take the following as an axiom:
∀A B C : prop, (A B)(B C)(A C)
Axiom. (eq_i_tra) We take the following as an axiom:
∀x y z, x = yy = zx = z
Axiom. (f_eq_i) We take the following as an axiom:
∀f : setset, ∀x y, x = yf x = f y
Axiom. (neq_i_sym) We take the following as an axiom:
∀x y, x yy x
Definition. We define nIn to be λx X ⇒ ¬ In x X of type setsetprop.
Notation. We use as an infix operator with priority 502 and no associativity corresponding to applying term nIn.
Axiom. (Eps_i_ex) We take the following as an axiom:
∀P : setprop, (∃x, P x)P (Eps_i P)
Axiom. (pred_ext) We take the following as an axiom:
∀P Q : setprop, (∀x, P x Q x)P = Q
Axiom. (prop_ext_2) We take the following as an axiom:
∀p q : prop, (pq)(qp)p = q
Axiom. (Subq_ref) We take the following as an axiom:
∀X : set, X X
Axiom. (Subq_tra) We take the following as an axiom:
∀X Y Z : set, X YY ZX Z
Axiom. (Subq_contra) We take the following as an axiom:
∀X Y z : set, X Yz Yz X
Axiom. (EmptyE) We take the following as an axiom:
∀x : set, x Empty
Axiom. (Subq_Empty) We take the following as an axiom:
∀X : set, Empty X
Axiom. (Empty_Subq_eq) We take the following as an axiom:
∀X : set, X EmptyX = Empty
Axiom. (Empty_eq) We take the following as an axiom:
∀X : set, (∀x, x X)X = Empty
Axiom. (UnionI) We take the following as an axiom:
∀X x Y : set, x YY Xx X
Axiom. (UnionE) We take the following as an axiom:
∀X x : set, x X∃Y : set, x Y Y X
Axiom. (UnionE_impred) We take the following as an axiom:
∀X x : set, x X∀p : prop, (∀Y : set, x YY Xp)p
Axiom. (PowerI) We take the following as an axiom:
∀X Y : set, Y XY 𝒫 X
Axiom. (PowerE) We take the following as an axiom:
∀X Y : set, Y 𝒫 XY X
Axiom. (Empty_In_Power) We take the following as an axiom:
∀X : set, Empty 𝒫 X
Axiom. (Self_In_Power) We take the following as an axiom:
∀X : set, X 𝒫 X
Axiom. (xm) We take the following as an axiom:
∀P : prop, P ¬ P
Axiom. (dneg) We take the following as an axiom:
∀P : prop, ¬ ¬ PP
Axiom. (not_all_ex_demorgan_i) We take the following as an axiom:
∀P : setprop, ¬ (∀x, P x)∃x, ¬ P x
Axiom. (eq_or_nand) We take the following as an axiom:
or = (λx y : prop¬ (¬ x ¬ y))
Primitive. The name exactly1of2 is a term of type proppropprop.
Axiom. (exactly1of2_I1) We take the following as an axiom:
∀A B : prop, A¬ Bexactly1of2 A B
Axiom. (exactly1of2_I2) We take the following as an axiom:
∀A B : prop, ¬ ABexactly1of2 A B
Axiom. (exactly1of2_E) We take the following as an axiom:
∀A B : prop, exactly1of2 A B∀p : prop, (A¬ Bp)(¬ ABp)p
Axiom. (exactly1of2_or) We take the following as an axiom:
∀A B : prop, exactly1of2 A BA B
Axiom. (ReplI) We take the following as an axiom:
∀A : set, ∀F : setset, ∀x : set, x AF x {F x|xA}
Axiom. (ReplE) We take the following as an axiom:
∀A : set, ∀F : setset, ∀y : set, y {F x|xA}∃xA, y = F x
Axiom. (ReplE_impred) We take the following as an axiom:
∀A : set, ∀F : setset, ∀y : set, y {F x|xA}∀p : prop, (∀x : set, x Ay = F xp)p
Axiom. (ReplE') We take the following as an axiom:
∀X, ∀f : setset, ∀p : setprop, (∀xX, p (f x))∀y{f x|xX}, p y
Axiom. (Repl_Empty) We take the following as an axiom:
∀F : setset, {F x|xEmpty} = Empty
Axiom. (ReplEq_ext_sub) We take the following as an axiom:
∀X, ∀F G : setset, (∀xX, F x = G x){F x|xX} {G x|xX}
Axiom. (ReplEq_ext) We take the following as an axiom:
∀X, ∀F G : setset, (∀xX, F x = G x){F x|xX} = {G x|xX}
Axiom. (Repl_inv_eq) We take the following as an axiom:
∀P : setprop, ∀f g : setset, (∀x, P xg (f x) = x)∀X, (∀xX, P x){g y|y{f x|xX}} = X
Axiom. (Repl_invol_eq) We take the following as an axiom:
∀P : setprop, ∀f : setset, (∀x, P xf (f x) = x)∀X, (∀xX, P x){f y|y{f x|xX}} = X
Primitive. The name If_i is a term of type propsetsetset.
Notation. if cond then T else E is notation corresponding to If_i type cond T E where type is the inferred type of T.
Axiom. (If_i_correct) We take the following as an axiom:
∀p : prop, ∀x y : set, p (if p then x else y) = x ¬ p (if p then x else y) = y
Axiom. (If_i_0) We take the following as an axiom:
∀p : prop, ∀x y : set, ¬ p(if p then x else y) = y
Axiom. (If_i_1) We take the following as an axiom:
∀p : prop, ∀x y : set, p(if p then x else y) = x
Axiom. (If_i_or) We take the following as an axiom:
∀p : prop, ∀x y : set, (if p then x else y) = x (if p then x else y) = y
Primitive. The name UPair is a term of type setsetset.
Notation. {x,y} is notation for UPair x y.
Axiom. (UPairE) We take the following as an axiom:
∀x y z : set, x {y,z}x = y x = z
Axiom. (UPairI1) We take the following as an axiom:
∀y z : set, y {y,z}
Axiom. (UPairI2) We take the following as an axiom:
∀y z : set, z {y,z}
Primitive. The name Sing is a term of type setset.
Notation. {x} is notation for Sing x.
Axiom. (SingI) We take the following as an axiom:
∀x : set, x {x}
Axiom. (SingE) We take the following as an axiom:
∀x y : set, y {x}y = x
Axiom. (Sing_inj) We take the following as an axiom:
∀x y, {x} = {y}x = y
Primitive. The name binunion is a term of type setsetset.
Notation. We use as an infix operator with priority 345 and which associates to the left corresponding to applying term binunion.
Axiom. (binunionI1) We take the following as an axiom:
∀X Y z : set, z Xz X Y
Axiom. (binunionI2) We take the following as an axiom:
∀X Y z : set, z Yz X Y
Axiom. (binunionE) We take the following as an axiom:
∀X Y z : set, z X Yz X z Y
Axiom. (binunionE') We take the following as an axiom:
∀X Y z, ∀p : prop, (z Xp)(z Yp)(z X Yp)
Axiom. (binunion_asso) We take the following as an axiom:
∀X Y Z : set, X (Y Z) = (X Y) Z
Axiom. (binunion_com_Subq) We take the following as an axiom:
∀X Y : set, X Y Y X
Axiom. (binunion_com) We take the following as an axiom:
∀X Y : set, X Y = Y X
Axiom. (binunion_idl) We take the following as an axiom:
∀X : set, Empty X = X
Axiom. (binunion_idr) We take the following as an axiom:
∀X : set, X Empty = X
Axiom. (binunion_Subq_1) We take the following as an axiom:
∀X Y : set, X X Y
Axiom. (binunion_Subq_2) We take the following as an axiom:
∀X Y : set, Y X Y
Axiom. (binunion_Subq_min) We take the following as an axiom:
∀X Y Z : set, X ZY ZX Y Z
Axiom. (Subq_binunion_eq) We take the following as an axiom:
∀X Y, (X Y) = (X Y = Y)
Definition. We define SetAdjoin to be λX y ⇒ X {y} of type setsetset.
Notation. We now use the set enumeration notation {...,...,...} in general. If 0 elements are given, then Empty is used to form the corresponding term. If 1 element is given, then Sing is used to form the corresponding term. If 2 elements are given, then UPair is used to form the corresponding term. If more than elements are given, then SetAdjoin is used to reduce to the case with one fewer elements.
Primitive. The name famunion is a term of type set(setset)set.
Notation. We use x [possibly with ascriptions] , B as a binder notation corresponding to a term constructed using famunion.
Axiom. (famunionI) We take the following as an axiom:
∀X : set, ∀F : (setset), ∀x y : set, x Xy F xy xXF x
Axiom. (famunionE) We take the following as an axiom:
∀X : set, ∀F : (setset), ∀y : set, y (xXF x)∃xX, y F x
Axiom. (famunionE_impred) We take the following as an axiom:
∀X : set, ∀F : (setset), ∀y : set, y (xXF x)∀p : prop, (∀x, x Xy F xp)p
Axiom. (famunion_Empty) We take the following as an axiom:
∀F : setset, (xEmptyF x) = Empty
Axiom. (famunion_Subq) We take the following as an axiom:
∀X, ∀f g : setset, (∀xX, f x g x)famunion X f famunion X g
Axiom. (famunion_ext) We take the following as an axiom:
∀X, ∀f g : setset, (∀xX, f x = g x)famunion X f = famunion X g
Beginning of Section SepSec
Variable X : set
Variable P : setprop
Let z : setEps_i (λz ⇒ z X P z)
Let F : setsetλx ⇒ if P x then x else z
Primitive. The name Sep is a term of type set.
End of Section SepSec
Notation. {xA | B} is notation for Sep Ax . B).
Axiom. (SepI) We take the following as an axiom:
∀X : set, ∀P : (setprop), ∀x : set, x XP xx {xX|P x}
Axiom. (SepE) We take the following as an axiom:
∀X : set, ∀P : (setprop), ∀x : set, x {xX|P x}x X P x
Axiom. (SepE1) We take the following as an axiom:
∀X : set, ∀P : (setprop), ∀x : set, x {xX|P x}x X
Axiom. (SepE2) We take the following as an axiom:
∀X : set, ∀P : (setprop), ∀x : set, x {xX|P x}P x
Axiom. (Sep_Empty) We take the following as an axiom:
∀P : setprop, {xEmpty|P x} = Empty
Axiom. (Sep_Subq) We take the following as an axiom:
∀X : set, ∀P : setprop, {xX|P x} X
Axiom. (Sep_In_Power) We take the following as an axiom:
∀X : set, ∀P : setprop, {xX|P x} 𝒫 X
Primitive. The name ReplSep is a term of type set(setprop)(setset)set.
Notation. {B| xA, C} is notation for ReplSep Ax . C) (λ x . B).
Axiom. (ReplSepI) We take the following as an axiom:
∀X : set, ∀P : setprop, ∀F : setset, ∀x : set, x XP xF x {F x|xX, P x}
Axiom. (ReplSepE) We take the following as an axiom:
∀X : set, ∀P : setprop, ∀F : setset, ∀y : set, y {F x|xX, P x}∃x : set, x X P x y = F x
Axiom. (ReplSepE_impred) We take the following as an axiom:
∀X : set, ∀P : setprop, ∀F : setset, ∀y : set, y {F x|xX, P x}∀p : prop, (∀xX, P xy = F xp)p
Primitive. The name binintersect is a term of type setsetset.
Notation. We use as an infix operator with priority 340 and which associates to the left corresponding to applying term binintersect.
Axiom. (binintersectI) We take the following as an axiom:
∀X Y z, z Xz Yz X Y
Axiom. (binintersectE) We take the following as an axiom:
∀X Y z, z X Yz X z Y
Axiom. (binintersectE1) We take the following as an axiom:
∀X Y z, z X Yz X
Axiom. (binintersectE2) We take the following as an axiom:
∀X Y z, z X Yz Y
Axiom. (binintersect_Subq_1) We take the following as an axiom:
∀X Y : set, X Y X
Axiom. (binintersect_Subq_2) We take the following as an axiom:
∀X Y : set, X Y Y
Axiom. (binintersect_Subq_eq_1) We take the following as an axiom:
∀X Y, X YX Y = X
Axiom. (binintersect_Subq_max) We take the following as an axiom:
∀X Y Z : set, Z XZ YZ X Y
Axiom. (binintersect_com_Subq) We take the following as an axiom:
∀X Y : set, X Y Y X
Axiom. (binintersect_com) We take the following as an axiom:
∀X Y : set, X Y = Y X
Primitive. The name setminus is a term of type setsetset.
Notation. We use as an infix operator with priority 350 and no associativity corresponding to applying term setminus.
Axiom. (setminusI) We take the following as an axiom:
∀X Y z, (z X)(z Y)z X Y
Axiom. (setminusE) We take the following as an axiom:
∀X Y z, (z X Y)z X z Y
Axiom. (setminusE1) We take the following as an axiom:
∀X Y z, (z X Y)z X
Axiom. (setminusE2) We take the following as an axiom:
∀X Y z, (z X Y)z Y
Axiom. (setminus_Subq) We take the following as an axiom:
∀X Y : set, X Y X
Axiom. (setminus_Subq_contra) We take the following as an axiom:
∀X Y Z : set, Z YX Y X Z
Axiom. (setminus_In_Power) We take the following as an axiom:
∀A U, A U 𝒫 A
Axiom. (setminus_idr) We take the following as an axiom:
∀X, X Empty = X
Axiom. (In_irref) We take the following as an axiom:
∀x, x x
Axiom. (In_no2cycle) We take the following as an axiom:
∀x y, x yy xFalse
Primitive. The name ordsucc is a term of type setset.
Axiom. (ordsuccI1) We take the following as an axiom:
∀x : set, x ordsucc x
Axiom. (ordsuccI2) We take the following as an axiom:
∀x : set, x ordsucc x
Axiom. (ordsuccE) We take the following as an axiom:
∀x y : set, y ordsucc xy x y = x
Notation. Natural numbers 0,1,2,... are notation for the terms formed using Empty as 0 and forming successors with ordsucc.
Axiom. (neq_0_ordsucc) We take the following as an axiom:
∀a : set, 0 ordsucc a
Axiom. (neq_ordsucc_0) We take the following as an axiom:
∀a : set, ordsucc a 0
Axiom. (ordsucc_inj) We take the following as an axiom:
∀a b : set, ordsucc a = ordsucc ba = b
Axiom. (ordsucc_inj_contra) We take the following as an axiom:
∀a b : set, a bordsucc a ordsucc b
Axiom. (In_0_1) We take the following as an axiom:
0 1
Axiom. (In_0_2) We take the following as an axiom:
0 2
Axiom. (In_1_2) We take the following as an axiom:
1 2
Axiom. (In_1_3) We take the following as an axiom:
1 3
Axiom. (In_2_3) We take the following as an axiom:
2 3
Axiom. (In_1_4) We take the following as an axiom:
1 4
Axiom. (In_2_4) We take the following as an axiom:
2 4
Axiom. (In_3_4) We take the following as an axiom:
3 4
Axiom. (In_1_5) We take the following as an axiom:
1 5
Axiom. (In_2_5) We take the following as an axiom:
2 5
Axiom. (In_3_5) We take the following as an axiom:
3 5
Axiom. (In_4_5) We take the following as an axiom:
4 5
Axiom. (In_1_6) We take the following as an axiom:
1 6
Axiom. (In_1_7) We take the following as an axiom:
1 7
Axiom. (In_1_8) We take the following as an axiom:
1 8
Definition. We define nat_p to be λn : set∀p : setprop, p 0(∀x : set, p xp (ordsucc x))p n of type setprop.
Axiom. (nat_0) We take the following as an axiom:
nat_p 0
Axiom. (nat_ordsucc) We take the following as an axiom:
∀n : set, nat_p nnat_p (ordsucc n)
Axiom. (nat_1) We take the following as an axiom:
nat_p 1
Axiom. (nat_2) We take the following as an axiom:
nat_p 2
Axiom. (nat_3) We take the following as an axiom:
nat_p 3
Axiom. (nat_4) We take the following as an axiom:
nat_p 4
Axiom. (nat_5) We take the following as an axiom:
nat_p 5
Axiom. (nat_6) We take the following as an axiom:
nat_p 6
Axiom. (nat_7) We take the following as an axiom:
nat_p 7
Axiom. (nat_8) We take the following as an axiom:
nat_p 8
Axiom. (nat_0_in_ordsucc) We take the following as an axiom:
∀n, nat_p n0 ordsucc n
Axiom. (nat_ordsucc_in_ordsucc) We take the following as an axiom:
∀n, nat_p n∀mn, ordsucc m ordsucc n
Axiom. (nat_ind) We take the following as an axiom:
∀p : setprop, p 0(∀n, nat_p np np (ordsucc n))∀n, nat_p np n
Axiom. (nat_inv_impred) We take the following as an axiom:
∀p : setprop, p 0(∀n, nat_p np (ordsucc n))∀n, nat_p np n
Axiom. (nat_inv) We take the following as an axiom:
∀n, nat_p nn = 0 ∃x, nat_p x n = ordsucc x
Axiom. (nat_complete_ind) We take the following as an axiom:
∀p : setprop, (∀n, nat_p n(∀mn, p m)p n)∀n, nat_p np n
Axiom. (nat_p_trans) We take the following as an axiom:
∀n, nat_p n∀mn, nat_p m
Axiom. (nat_trans) We take the following as an axiom:
∀n, nat_p n∀mn, m n
Axiom. (nat_ordsucc_trans) We take the following as an axiom:
∀n, nat_p n∀mordsucc n, m n
Axiom. (Union_ordsucc_eq) We take the following as an axiom:
∀n, nat_p n (ordsucc n) = n
Axiom. (cases_1) We take the following as an axiom:
∀i1, ∀p : setprop, p 0p i
Axiom. (cases_2) We take the following as an axiom:
∀i2, ∀p : setprop, p 0p 1p i
Axiom. (cases_3) We take the following as an axiom:
∀i3, ∀p : setprop, p 0p 1p 2p i
Axiom. (neq_0_1) We take the following as an axiom:
0 1
Axiom. (neq_1_0) We take the following as an axiom:
1 0
Axiom. (neq_0_2) We take the following as an axiom:
0 2
Axiom. (neq_2_0) We take the following as an axiom:
2 0
Axiom. (neq_1_2) We take the following as an axiom:
1 2
Axiom. (neq_1_3) We take the following as an axiom:
1 3
Axiom. (neq_2_3) We take the following as an axiom:
2 3
Axiom. (neq_2_4) We take the following as an axiom:
2 4
Axiom. (neq_3_4) We take the following as an axiom:
3 4
Axiom. (ZF_closed_E) We take the following as an axiom:
∀U, ZF_closed U∀p : prop, (Union_closed UPower_closed URepl_closed Up)p
Axiom. (ZF_Union_closed) We take the following as an axiom:
∀U, ZF_closed U∀XU, X U
Axiom. (ZF_Power_closed) We take the following as an axiom:
∀U, ZF_closed U∀XU, 𝒫 X U
Axiom. (ZF_Repl_closed) We take the following as an axiom:
∀U, ZF_closed U∀XU, ∀F : setset, (∀xX, F x U){F x|xX} U
Axiom. (ZF_UPair_closed) We take the following as an axiom:
∀U, ZF_closed U∀x yU, {x,y} U
Axiom. (ZF_Sing_closed) We take the following as an axiom:
∀U, ZF_closed U∀xU, {x} U
Axiom. (ZF_binunion_closed) We take the following as an axiom:
∀U, ZF_closed U∀X YU, (X Y) U
Axiom. (ZF_ordsucc_closed) We take the following as an axiom:
∀U, ZF_closed U∀xU, ordsucc x U
Axiom. (nat_p_UnivOf_Empty) We take the following as an axiom:
∀n : set, nat_p nn UnivOf Empty
Primitive. The name ω is a term of type set.
Axiom. (omega_nat_p) We take the following as an axiom:
∀nω, nat_p n
Axiom. (nat_p_omega) We take the following as an axiom:
∀n : set, nat_p nn ω
Axiom. (omega_ordsucc) We take the following as an axiom:
∀nω, ordsucc n ω
Definition. We define ordinal to be λalpha : setTransSet alpha ∀betaalpha, TransSet beta of type setprop.
Axiom. (ordinal_TransSet) We take the following as an axiom:
∀alpha : set, ordinal alphaTransSet alpha
Axiom. (ordinal_Empty) We take the following as an axiom:
ordinal Empty
Axiom. (ordinal_Hered) We take the following as an axiom:
∀alpha : set, ordinal alpha∀betaalpha, ordinal beta
Axiom. (TransSet_ordsucc) We take the following as an axiom:
∀X : set, TransSet XTransSet (ordsucc X)
Axiom. (ordinal_ordsucc) We take the following as an axiom:
∀alpha : set, ordinal alphaordinal (ordsucc alpha)
Axiom. (nat_p_ordinal) We take the following as an axiom:
∀n : set, nat_p nordinal n
Axiom. (ordinal_1) We take the following as an axiom:
ordinal 1
Axiom. (ordinal_2) We take the following as an axiom:
ordinal 2
Axiom. (omega_TransSet) We take the following as an axiom:
TransSet ω
Axiom. (omega_ordinal) We take the following as an axiom:
ordinal ω
Axiom. (ordsucc_omega_ordinal) We take the following as an axiom:
ordinal (ordsucc ω)
Axiom. (TransSet_ordsucc_In_Subq) We take the following as an axiom:
∀X : set, TransSet X∀xX, ordsucc x X
Axiom. (ordinal_ordsucc_In_Subq) We take the following as an axiom:
∀alpha, ordinal alpha∀betaalpha, ordsucc beta alpha
Axiom. (ordinal_trichotomy_or) We take the following as an axiom:
∀alpha beta : set, ordinal alphaordinal betaalpha beta alpha = beta beta alpha
Axiom. (ordinal_trichotomy_or_impred) We take the following as an axiom:
∀alpha beta : set, ordinal alphaordinal beta∀p : prop, (alpha betap)(alpha = betap)(beta alphap)p
Axiom. (ordinal_In_Or_Subq) We take the following as an axiom:
∀alpha beta, ordinal alphaordinal betaalpha beta beta alpha
Axiom. (ordinal_linear) We take the following as an axiom:
∀alpha beta, ordinal alphaordinal betaalpha beta beta alpha
Axiom. (ordinal_ordsucc_In_eq) We take the following as an axiom:
∀alpha beta, ordinal alphabeta alphaordsucc beta alpha alpha = ordsucc beta
Axiom. (ordinal_lim_or_succ) We take the following as an axiom:
∀alpha, ordinal alpha(∀betaalpha, ordsucc beta alpha) (∃betaalpha, alpha = ordsucc beta)
Axiom. (ordinal_ordsucc_In) We take the following as an axiom:
∀alpha, ordinal alpha∀betaalpha, ordsucc beta ordsucc alpha
Axiom. (ordinal_famunion) We take the following as an axiom:
∀X, ∀F : setset, (∀xX, ordinal (F x))ordinal (xXF x)
Axiom. (ordinal_binintersect) We take the following as an axiom:
∀alpha beta, ordinal alphaordinal betaordinal (alpha beta)
Axiom. (ordinal_binunion) We take the following as an axiom:
∀alpha beta, ordinal alphaordinal betaordinal (alpha beta)
Axiom. (ordinal_ind) We take the following as an axiom:
∀p : setprop, (∀alpha, ordinal alpha(∀betaalpha, p beta)p alpha)∀alpha, ordinal alphap alpha
Axiom. (least_ordinal_ex) We take the following as an axiom:
∀p : setprop, (∃alpha, ordinal alpha p alpha)∃alpha, ordinal alpha p alpha ∀betaalpha, ¬ p beta
Definition. We define inj to be λX Y f ⇒ (∀uX, f u Y) (∀u vX, f u = f vu = v) of type setset(setset)prop.
Definition. We define bij to be λX Y f ⇒ (∀uX, f u Y) (∀u vX, f u = f vu = v) (∀wY, ∃uX, f u = w) of type setset(setset)prop.
Axiom. (bijI) We take the following as an axiom:
∀X Y, ∀f : setset, (∀uX, f u Y)(∀u vX, f u = f vu = v)(∀wY, ∃uX, f u = w)bij X Y f
Axiom. (bijE) We take the following as an axiom:
∀X Y, ∀f : setset, bij X Y f∀p : prop, ((∀uX, f u Y)(∀u vX, f u = f vu = v)(∀wY, ∃uX, f u = w)p)p
Primitive. The name inv is a term of type set(setset)setset.
Axiom. (surj_rinv) We take the following as an axiom:
∀X Y, ∀f : setset, (∀wY, ∃uX, f u = w)∀yY, inv X f y X f (inv X f y) = y
Axiom. (inj_linv) We take the following as an axiom:
∀X, ∀f : setset, (∀u vX, f u = f vu = v)∀xX, inv X f (f x) = x
Axiom. (bij_inv) We take the following as an axiom:
∀X Y, ∀f : setset, bij X Y fbij Y X (inv X f)
Axiom. (bij_id) We take the following as an axiom:
∀X, bij X X (λx ⇒ x)
Axiom. (bij_comp) We take the following as an axiom:
∀X Y Z : set, ∀f g : setset, bij X Y fbij Y Z gbij X Z (λx ⇒ g (f x))
Definition. We define equip to be λX Y : set∃f : setset, bij X Y f of type setsetprop.
Axiom. (equip_ref) We take the following as an axiom:
∀X, equip X X
Axiom. (equip_sym) We take the following as an axiom:
∀X Y, equip X Yequip Y X
Axiom. (equip_tra) We take the following as an axiom:
∀X Y Z, equip X Yequip Y Zequip X Z
Axiom. (equip_0_Empty) We take the following as an axiom:
∀X, equip X 0X = 0
Beginning of Section SchroederBernstein
Axiom. (KnasterTarski_set) We take the following as an axiom:
∀A, ∀F : setset, (∀U𝒫 A, F U 𝒫 A)(∀U V𝒫 A, U VF U F V)∃Y𝒫 A, F Y = Y
Axiom. (image_In_Power) We take the following as an axiom:
∀A B, ∀f : setset, (∀xA, f x B)∀U𝒫 A, {f x|xU} 𝒫 B
Axiom. (image_monotone) We take the following as an axiom:
∀f : setset, ∀U V, U V{f x|xU} {f x|xV}
Axiom. (setminus_antimonotone) We take the following as an axiom:
∀A U V, U VA V A U
Axiom. (SchroederBernstein) We take the following as an axiom:
∀A B, ∀f g : setset, inj A B finj B A gequip A B
End of Section SchroederBernstein
Beginning of Section PigeonHole
Axiom. (PigeonHole_nat) We take the following as an axiom:
∀n, nat_p n∀f : setset, (∀iordsucc n, f i n)¬ (∀i jordsucc n, f i = f ji = j)
Axiom. (PigeonHole_nat_bij) We take the following as an axiom:
∀n, nat_p n∀f : setset, (∀in, f i n)(∀i jn, f i = f ji = j)bij n n f
End of Section PigeonHole
Definition. We define finite to be λX ⇒ ∃nω, equip X n of type setprop.
Axiom. (finite_ind) We take the following as an axiom:
∀p : setprop, p Empty(∀X y, finite Xy Xp Xp (X {y}))∀X, finite Xp X
Axiom. (finite_Empty) We take the following as an axiom:
finite 0
Axiom. (adjoin_finite) We take the following as an axiom:
∀X y, finite Xfinite (X {y})
Axiom. (binunion_finite) We take the following as an axiom:
∀X, finite X∀Y, finite Yfinite (X Y)
Axiom. (famunion_nat_finite) We take the following as an axiom:
∀X : setset, ∀n, nat_p n(∀in, finite (X i))finite (inX i)
Axiom. (Subq_finite) We take the following as an axiom:
∀X, finite X∀Y, Y Xfinite Y
Axiom. (TransSet_In_ordsucc_Subq) We take the following as an axiom:
∀x y, TransSet yx ordsucc yx y
Axiom. (exandE_i) We take the following as an axiom:
∀P Q : setprop, (∃x, P x Q x)∀r : prop, (∀x, P xQ xr)r
Axiom. (exandE_ii) We take the following as an axiom:
∀P Q : (setset)prop, (∃x : setset, P x Q x)∀p : prop, (∀x : setset, P xQ xp)p
Axiom. (exandE_iii) We take the following as an axiom:
∀P Q : (setsetset)prop, (∃x : setsetset, P x Q x)∀p : prop, (∀x : setsetset, P xQ xp)p
Axiom. (exandE_iiii) We take the following as an axiom:
∀P Q : (setsetsetset)prop, (∃x : setsetsetset, P x Q x)∀p : prop, (∀x : setsetsetset, P xQ xp)p
Beginning of Section Descr_ii
Variable P : (setset)prop
Primitive. The name Descr_ii is a term of type setset.
Hypothesis Pex : ∃f : setset, P f
Hypothesis Puniq : ∀f g : setset, P fP gf = g
Axiom. (Descr_ii_prop) We take the following as an axiom:
End of Section Descr_ii
Beginning of Section Descr_iii
Variable P : (setsetset)prop
Primitive. The name Descr_iii is a term of type setsetset.
Hypothesis Pex : ∃f : setsetset, P f
Hypothesis Puniq : ∀f g : setsetset, P fP gf = g
Axiom. (Descr_iii_prop) We take the following as an axiom:
End of Section Descr_iii
Beginning of Section Descr_Vo1
Variable P : Vo 1prop
Primitive. The name Descr_Vo1 is a term of type Vo 1.
Hypothesis Pex : ∃f : Vo 1, P f
Hypothesis Puniq : ∀f g : Vo 1, P fP gf = g
Axiom. (Descr_Vo1_prop) We take the following as an axiom:
End of Section Descr_Vo1
Beginning of Section If_ii
Variable p : prop
Variable f g : setset
Primitive. The name If_ii is a term of type setset.
Axiom. (If_ii_1) We take the following as an axiom:
pIf_ii = f
Axiom. (If_ii_0) We take the following as an axiom:
¬ pIf_ii = g
End of Section If_ii
Beginning of Section If_iii
Variable p : prop
Variable f g : setsetset
Primitive. The name If_iii is a term of type setsetset.
Axiom. (If_iii_1) We take the following as an axiom:
pIf_iii = f
Axiom. (If_iii_0) We take the following as an axiom:
¬ pIf_iii = g
End of Section If_iii
Beginning of Section EpsilonRec_i
Variable F : set(setset)set
Definition. We define In_rec_i_G to be λX Y ⇒ ∀R : setsetprop, (∀X : set, ∀f : setset, (∀xX, R x (f x))R X (F X f))R X Y of type setsetprop.
Primitive. The name In_rec_i is a term of type setset.
Axiom. (In_rec_i_G_c) We take the following as an axiom:
∀X : set, ∀f : setset, (∀xX, In_rec_i_G x (f x))In_rec_i_G X (F X f)
Axiom. (In_rec_i_G_inv) We take the following as an axiom:
∀X : set, ∀Y : set, In_rec_i_G X Y∃f : setset, (∀xX, In_rec_i_G x (f x)) Y = F X f
Hypothesis Fr : ∀X : set, ∀g h : setset, (∀xX, g x = h x)F X g = F X h
Axiom. (In_rec_i_G_f) We take the following as an axiom:
∀X : set, ∀Y Z : set, In_rec_i_G X YIn_rec_i_G X ZY = Z
Axiom. (In_rec_i_G_In_rec_i) We take the following as an axiom:
∀X : set, In_rec_i_G X (In_rec_i X)
Axiom. (In_rec_i_G_In_rec_i_d) We take the following as an axiom:
∀X : set, In_rec_i_G X (F X In_rec_i)
Axiom. (In_rec_i_eq) We take the following as an axiom:
∀X : set, In_rec_i X = F X In_rec_i
End of Section EpsilonRec_i
Beginning of Section EpsilonRec_ii
Variable F : set(set(setset))(setset)
Definition. We define In_rec_G_ii to be λX Y ⇒ ∀R : set(setset)prop, (∀X : set, ∀f : set(setset), (∀xX, R x (f x))R X (F X f))R X Y of type set(setset)prop.
Primitive. The name In_rec_ii is a term of type set(setset).
Axiom. (In_rec_G_ii_c) We take the following as an axiom:
∀X : set, ∀f : set(setset), (∀xX, In_rec_G_ii x (f x))In_rec_G_ii X (F X f)
Axiom. (In_rec_G_ii_inv) We take the following as an axiom:
∀X : set, ∀Y : (setset), In_rec_G_ii X Y∃f : set(setset), (∀xX, In_rec_G_ii x (f x)) Y = F X f
Hypothesis Fr : ∀X : set, ∀g h : set(setset), (∀xX, g x = h x)F X g = F X h
Axiom. (In_rec_G_ii_f) We take the following as an axiom:
∀X : set, ∀Y Z : (setset), In_rec_G_ii X YIn_rec_G_ii X ZY = Z
Axiom. (In_rec_G_ii_In_rec_ii) We take the following as an axiom:
∀X : set, In_rec_G_ii X (In_rec_ii X)
Axiom. (In_rec_G_ii_In_rec_ii_d) We take the following as an axiom:
∀X : set, In_rec_G_ii X (F X In_rec_ii)
Axiom. (In_rec_ii_eq) We take the following as an axiom:
∀X : set, In_rec_ii X = F X In_rec_ii
End of Section EpsilonRec_ii
Beginning of Section EpsilonRec_iii
Variable F : set(set(setsetset))(setsetset)
Definition. We define In_rec_G_iii to be λX Y ⇒ ∀R : set(setsetset)prop, (∀X : set, ∀f : set(setsetset), (∀xX, R x (f x))R X (F X f))R X Y of type set(setsetset)prop.
Primitive. The name In_rec_iii is a term of type set(setsetset).
Axiom. (In_rec_G_iii_c) We take the following as an axiom:
∀X : set, ∀f : set(setsetset), (∀xX, In_rec_G_iii x (f x))In_rec_G_iii X (F X f)
Axiom. (In_rec_G_iii_inv) We take the following as an axiom:
∀X : set, ∀Y : (setsetset), In_rec_G_iii X Y∃f : set(setsetset), (∀xX, In_rec_G_iii x (f x)) Y = F X f
Hypothesis Fr : ∀X : set, ∀g h : set(setsetset), (∀xX, g x = h x)F X g = F X h
Axiom. (In_rec_G_iii_f) We take the following as an axiom:
∀X : set, ∀Y Z : (setsetset), In_rec_G_iii X YIn_rec_G_iii X ZY = Z
Axiom. (In_rec_G_iii_In_rec_iii) We take the following as an axiom:
∀X : set, In_rec_G_iii X (In_rec_iii X)
Axiom. (In_rec_G_iii_In_rec_iii_d) We take the following as an axiom:
∀X : set, In_rec_G_iii X (F X In_rec_iii)
Axiom. (In_rec_iii_eq) We take the following as an axiom:
∀X : set, In_rec_iii X = F X In_rec_iii
End of Section EpsilonRec_iii
Beginning of Section NatRec
Variable z : set
Variable f : setsetset
Let F : set(setset)setλn g ⇒ if n n then f ( n) (g ( n)) else z
Definition. We define nat_primrec to be In_rec_i F of type setset.
Axiom. (nat_primrec_r) We take the following as an axiom:
∀X : set, ∀g h : setset, (∀xX, g x = h x)F X g = F X h
Axiom. (nat_primrec_0) We take the following as an axiom:
Axiom. (nat_primrec_S) We take the following as an axiom:
∀n : set, nat_p nnat_primrec (ordsucc n) = f n (nat_primrec n)
End of Section NatRec
Beginning of Section NatArith
Definition. We define add_nat to be λn m : setnat_primrec n (λ_ r ⇒ ordsucc r) m of type setsetset.
Notation. We use + as an infix operator with priority 360 and which associates to the right corresponding to applying term add_nat.
Axiom. (add_nat_0R) We take the following as an axiom:
∀n : set, n + 0 = n
Axiom. (add_nat_SR) We take the following as an axiom:
∀n m : set, nat_p mn + ordsucc m = ordsucc (n + m)
Axiom. (add_nat_p) We take the following as an axiom:
∀n : set, nat_p n∀m : set, nat_p mnat_p (n + m)
Axiom. (add_nat_1_1_2) We take the following as an axiom:
1 + 1 = 2
Axiom. (add_nat_0L) We take the following as an axiom:
∀m : set, nat_p m0 + m = m
Axiom. (add_nat_SL) We take the following as an axiom:
∀n : set, nat_p n∀m : set, nat_p mordsucc n + m = ordsucc (n + m)
Axiom. (add_nat_com) We take the following as an axiom:
∀n : set, nat_p n∀m : set, nat_p mn + m = m + n
Axiom. (nat_Subq_add_ex) We take the following as an axiom:
∀n, nat_p n∀m, nat_p mn m∃k, nat_p k m = k + n
Definition. We define mul_nat to be λn m : setnat_primrec 0 (λ_ r ⇒ n + r) m of type setsetset.
Notation. We use * as an infix operator with priority 355 and which associates to the right corresponding to applying term mul_nat.
Axiom. (mul_nat_0R) We take the following as an axiom:
∀n : set, n * 0 = 0
Axiom. (mul_nat_SR) We take the following as an axiom:
∀n m : set, nat_p mn * ordsucc m = n + n * m
Axiom. (mul_nat_p) We take the following as an axiom:
∀n : set, nat_p n∀m : set, nat_p mnat_p (n * m)
End of Section NatArith
Definition. We define Inj1 to be In_rec_i (λX f ⇒ {0} {f x|xX}) of type setset.
Axiom. (Inj1_eq) We take the following as an axiom:
∀X : set, Inj1 X = {0} {Inj1 x|xX}
Axiom. (Inj1I1) We take the following as an axiom:
∀X : set, 0 Inj1 X
Axiom. (Inj1I2) We take the following as an axiom:
∀X x : set, x XInj1 x Inj1 X
Axiom. (Inj1E) We take the following as an axiom:
∀X y : set, y Inj1 Xy = 0 ∃xX, y = Inj1 x
Axiom. (Inj1NE1) We take the following as an axiom:
∀x : set, Inj1 x 0
Axiom. (Inj1NE2) We take the following as an axiom:
∀x : set, Inj1 x {0}
Definition. We define Inj0 to be λX ⇒ {Inj1 x|xX} of type setset.
Axiom. (Inj0I) We take the following as an axiom:
∀X x : set, x XInj1 x Inj0 X
Axiom. (Inj0E) We take the following as an axiom:
∀X y : set, y Inj0 X∃x : set, x X y = Inj1 x
Definition. We define Unj to be In_rec_i (λX f ⇒ {f x|xX {0}}) of type setset.
Axiom. (Unj_eq) We take the following as an axiom:
∀X : set, Unj X = {Unj x|xX {0}}
Axiom. (Unj_Inj1_eq) We take the following as an axiom:
∀X : set, Unj (Inj1 X) = X
Axiom. (Inj1_inj) We take the following as an axiom:
∀X Y : set, Inj1 X = Inj1 YX = Y
Axiom. (Unj_Inj0_eq) We take the following as an axiom:
∀X : set, Unj (Inj0 X) = X
Axiom. (Inj0_inj) We take the following as an axiom:
∀X Y : set, Inj0 X = Inj0 YX = Y
Axiom. (Inj0_0) We take the following as an axiom:
Inj0 0 = 0
Axiom. (Inj0_Inj1_neq) We take the following as an axiom:
∀X Y : set, Inj0 X Inj1 Y
Definition. We define setsum to be λX Y ⇒ {Inj0 x|xX} {Inj1 y|yY} of type setsetset.
Notation. We use + as an infix operator with priority 450 and which associates to the left corresponding to applying term setsum.
Axiom. (Inj0_setsum) We take the following as an axiom:
∀X Y x : set, x XInj0 x X + Y
Axiom. (Inj1_setsum) We take the following as an axiom:
∀X Y y : set, y YInj1 y X + Y
Axiom. (setsum_Inj_inv) We take the following as an axiom:
∀X Y z : set, z X + Y(∃xX, z = Inj0 x) (∃yY, z = Inj1 y)
Axiom. (Inj0_setsum_0L) We take the following as an axiom:
∀X : set, 0 + X = Inj0 X
Axiom. (Subq_1_Sing0) We take the following as an axiom:
1 {0}
Axiom. (Subq_Sing0_1) We take the following as an axiom:
{0} 1
Axiom. (eq_1_Sing0) We take the following as an axiom:
1 = {0}
Axiom. (Inj1_setsum_1L) We take the following as an axiom:
∀X : set, 1 + X = Inj1 X
Axiom. (nat_setsum1_ordsucc) We take the following as an axiom:
∀n : set, nat_p n1 + n = ordsucc n
Axiom. (setsum_0_0) We take the following as an axiom:
0 + 0 = 0
Axiom. (setsum_1_0_1) We take the following as an axiom:
1 + 0 = 1
Axiom. (setsum_1_1_2) We take the following as an axiom:
1 + 1 = 2
Beginning of Section pair_setsum
Let pair ≝ setsum
Definition. We define proj0 to be λZ ⇒ {Unj z|zZ, ∃x : set, Inj0 x = z} of type setset.
Definition. We define proj1 to be λZ ⇒ {Unj z|zZ, ∃y : set, Inj1 y = z} of type setset.
Axiom. (Inj0_pair_0_eq) We take the following as an axiom:
Inj0 = pair 0
Axiom. (Inj1_pair_1_eq) We take the following as an axiom:
Inj1 = pair 1
Axiom. (pairI0) We take the following as an axiom:
∀X Y x, x Xpair 0 x pair X Y
Axiom. (pairI1) We take the following as an axiom:
∀X Y y, y Ypair 1 y pair X Y
Axiom. (pairE) We take the following as an axiom:
∀X Y z, z pair X Y(∃xX, z = pair 0 x) (∃yY, z = pair 1 y)
Axiom. (pairE0) We take the following as an axiom:
∀X Y x, pair 0 x pair X Yx X
Axiom. (pairE1) We take the following as an axiom:
∀X Y y, pair 1 y pair X Yy Y
Axiom. (proj0I) We take the following as an axiom:
∀w u : set, pair 0 u wu proj0 w
Axiom. (proj0E) We take the following as an axiom:
∀w u : set, u proj0 wpair 0 u w
Axiom. (proj1I) We take the following as an axiom:
∀w u : set, pair 1 u wu proj1 w
Axiom. (proj1E) We take the following as an axiom:
∀w u : set, u proj1 wpair 1 u w
Axiom. (proj0_pair_eq) We take the following as an axiom:
∀X Y : set, proj0 (pair X Y) = X
Axiom. (proj1_pair_eq) We take the following as an axiom:
∀X Y : set, proj1 (pair X Y) = Y
Definition. We define Sigma to be λX Y ⇒ xX{pair x y|yY x} of type set(setset)set.
Notation. We use x...y [possibly with ascriptions] , B as a binder notation corresponding to a term constructed using Sigma.
Axiom. (pair_Sigma) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀xX, ∀yY x, pair x y xX, Y x
Axiom. (Sigma_eta_proj0_proj1) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀z(xX, Y x), pair (proj0 z) (proj1 z) = z proj0 z X proj1 z Y (proj0 z)
Axiom. (proj_Sigma_eta) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀z(xX, Y x), pair (proj0 z) (proj1 z) = z
Axiom. (proj0_Sigma) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀z : set, z (xX, Y x)proj0 z X
Axiom. (proj1_Sigma) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀z : set, z (xX, Y x)proj1 z Y (proj0 z)
Axiom. (pair_Sigma_E1) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀x y : set, pair x y (xX, Y x)y Y x
Axiom. (Sigma_E) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀z : set, z (xX, Y x)∃xX, ∃yY x, z = pair x y
Definition. We define setprod to be λX Y : setxX, Y of type setsetset.
Notation. We use as an infix operator with priority 440 and which associates to the left corresponding to applying term setprod.
Let lam : set(setset)setSigma
Definition. We define ap to be λf x ⇒ {proj1 z|zf, ∃y : set, z = pair x y} of type setsetset.
Notation. When x is a set, a term x y is notation for ap x y.
Notation. λ xAB is notation for the set Sigma Ax : set ⇒ B).
Notation. We now use n-tuple notation (a0,...,an-1) for n ≥ 2 for λ i ∈ n . if i = 0 then a0 else ... if i = n-2 then an-2 else an-1.
Axiom. (lamI) We take the following as an axiom:
∀X : set, ∀F : setset, ∀xX, ∀yF x, pair x y λxXF x
Axiom. (lamE) We take the following as an axiom:
∀X : set, ∀F : setset, ∀z : set, z (λxXF x)∃xX, ∃yF x, z = pair x y
Axiom. (apI) We take the following as an axiom:
∀f x y, pair x y fy f x
Axiom. (apE) We take the following as an axiom:
∀f x y, y f xpair x y f
Axiom. (beta) We take the following as an axiom:
∀X : set, ∀F : setset, ∀x : set, x X(λxXF x) x = F x
Axiom. (proj0_ap_0) We take the following as an axiom:
∀u, proj0 u = u 0
Axiom. (proj1_ap_1) We take the following as an axiom:
∀u, proj1 u = u 1
Axiom. (pair_ap_0) We take the following as an axiom:
∀x y : set, (pair x y) 0 = x
Axiom. (pair_ap_1) We take the following as an axiom:
∀x y : set, (pair x y) 1 = y
Axiom. (ap0_Sigma) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀z : set, z (xX, Y x)(z 0) X
Axiom. (ap1_Sigma) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀z : set, z (xX, Y x)(z 1) (Y (z 0))
Definition. We define pair_p to be λu : setpair (u 0) (u 1) = u of type setprop.
Axiom. (pair_p_I) We take the following as an axiom:
∀x y, pair_p (pair x y)
Axiom. (Subq_2_UPair01) We take the following as an axiom:
Axiom. (tuple_pair) We take the following as an axiom:
∀x y : set, pair x y = (x,y)
Definition. We define Pi to be λX Y ⇒ {f𝒫 (xX, (Y x))|∀xX, f x Y x} of type set(setset)set.
Notation. We use x...y [possibly with ascriptions] , B as a binder notation corresponding to a term constructed using Pi.
Axiom. (PiI) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀f : set, (∀uf, pair_p u u 0 X)(∀xX, f x Y x)f xX, Y x
Axiom. (lam_Pi) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀F : setset, (∀xX, F x Y x)(λxXF x) (xX, Y x)
Axiom. (ap_Pi) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀f : set, ∀x : set, f (xX, Y x)x Xf x Y x
Definition. We define setexp to be λX Y : setyY, X of type setsetset.
Notation. We use :^: as an infix operator with priority 430 and which associates to the left corresponding to applying term setexp.
Axiom. (pair_tuple_fun) We take the following as an axiom:
pair = (λx y ⇒ (x,y))
Axiom. (lamI2) We take the following as an axiom:
∀X, ∀F : setset, ∀xX, ∀yF x, (x,y) λxXF x
Beginning of Section Tuples
Variable x0 x1 : set
Axiom. (tuple_2_0_eq) We take the following as an axiom:
(x0,x1) 0 = x0
Axiom. (tuple_2_1_eq) We take the following as an axiom:
(x0,x1) 1 = x1
End of Section Tuples
Axiom. (ReplEq_setprod_ext) We take the following as an axiom:
∀X Y, ∀F G : setsetset, (∀xX, ∀yY, F x y = G x y){F (w 0) (w 1)|wX Y} = {G (w 0) (w 1)|wX Y}
Axiom. (tuple_2_Sigma) We take the following as an axiom:
∀X : set, ∀Y : setset, ∀xX, ∀yY x, (x,y) xX, Y x
Axiom. (tuple_2_setprod) We take the following as an axiom:
∀X : set, ∀Y : set, ∀xX, ∀yY, (x,y) X Y
End of Section pair_setsum