Mercurial > hg > Members > kono > Proof > ZF-in-agda
diff OD.agda @ 277:d9d3654baee1
seperate choice from LEM
author | Shinji KONO <kono@ie.u-ryukyu.ac.jp> |
---|---|
date | Sat, 09 May 2020 09:38:21 +0900 |
parents | 6f10c47e4e7a |
children | 5de8905a5a2b 359402cc6c3d |
line wrap: on
line diff
--- a/OD.agda Sat May 09 09:02:52 2020 +0900 +++ b/OD.agda Sat May 09 09:38:21 2020 +0900 @@ -52,6 +52,40 @@ eq→ ( ⇔→== {x} {y} eq ) {z} m = proj1 eq m eq← ( ⇔→== {x} {y} eq ) {z} m = proj2 eq m +-- next assumptions are our axiom +-- it defines a subset of OD, which is called HOD, usually defined as +-- HOD = { x | TC x ⊆ OD } +-- where TC x is a transitive clusure of x, i.e. Union of all elemnts of all subset of x + +record ODAxiom : Set (suc n) where + -- OD can be iso to a subset of Ordinal ( by means of Godel Set ) + field + od→ord : OD → Ordinal + ord→od : Ordinal → OD + c<→o< : {x y : OD } → def y ( od→ord x ) → od→ord x o< od→ord y + oiso : {x : OD } → ord→od ( od→ord x ) ≡ x + diso : {x : Ordinal } → od→ord ( ord→od x ) ≡ x + ==→o≡ : { x y : OD } → (x == y) → x ≡ y + -- supermum as Replacement Axiom ( corresponding Ordinal of OD has maximum ) + sup-o : ( OD → Ordinal ) → Ordinal + sup-o< : { ψ : OD → Ordinal } → ∀ {x : OD } → ψ x o< sup-o ψ + -- contra-position of mimimulity of supermum required in Power Set Axiom which we don't use + -- sup-x : {n : Level } → ( OD → Ordinal ) → Ordinal + -- sup-lb : {n : Level } → { ψ : OD → Ordinal } → {z : Ordinal } → z o< sup-o ψ → z o< osuc (ψ (sup-x ψ)) + +postulate odAxiom : ODAxiom +open ODAxiom odAxiom + +data One : Set n where + OneObj : One + +-- Ordinals in OD , the maximum +Ords : OD +Ords = record { def = λ x → One } + +maxod : {x : OD} → od→ord x o< od→ord Ords +maxod {x} = c<→o< OneObj + -- Ordinal in OD ( and ZFSet ) Transitive Set Ord : ( a : Ordinal ) → OD Ord a = record { def = λ y → y o< a } @@ -59,37 +93,6 @@ od∅ : OD od∅ = Ord o∅ --- next assumptions are our axiom --- it defines a subset of OD, which is called HOD, usually defined as --- HOD = { x | TC x ⊆ OD } --- where TC x is a transitive clusure of x, i.e. Union of all elemnts of all subset of x - -postulate - -- OD can be iso to a subset of Ordinal ( by means of Godel Set ) - od→ord : OD → Ordinal - ord→od : Ordinal → OD - c<→o< : {x y : OD } → def y ( od→ord x ) → od→ord x o< od→ord y - oiso : {x : OD } → ord→od ( od→ord x ) ≡ x - diso : {x : Ordinal } → od→ord ( ord→od x ) ≡ x - ==→o≡ : { x y : OD } → (x == y) → x ≡ y - -- next assumption causes ∀ x ∋ ∅ . It menas only an ordinal is allowed as OD - -- o<→c< : {n : Level} {x y : Ordinal } → x o< y → def (ord→od y) x - -- ord→od x ≡ Ord x results the same - -- supermum as Replacement Axiom ( corresponding Ordinal of OD has maximum ) - sup-o : ( OD → Ordinal ) → Ordinal - sup-o< : { ψ : OD → Ordinal } → ∀ {x : OD } → ψ x o< sup-o ψ - -- contra-position of mimimulity of supermum required in Power Set Axiom - -- sup-x : {n : Level } → ( Ordinal → Ordinal ) → Ordinal - -- sup-lb : {n : Level } → { ψ : Ordinal → Ordinal } → {z : Ordinal } → z o< sup-o ψ → z o< osuc (ψ (sup-x ψ)) - -data One : Set n where - OneObj : One - -Ords : OD -Ords = record { def = λ x → One } - -maxod : {x : OD} → od→ord x o< od→ord Ords -maxod {x} = c<→o< OneObj o<→c<→OD=Ord : ( {x y : Ordinal } → x o< y → def (ord→od y) x ) → {x : OD } → x ≡ Ord (od→ord x) o<→c<→OD=Ord o<→c< {x} = ==→o≡ ( record { eq→ = lemma1 ; eq← = lemma2 } ) where @@ -256,8 +259,8 @@ A ∈ B = B ∋ A Power : OD → OD Power A = Replace (Def (Ord (od→ord A))) ( λ x → A ∩ x ) - {_} : ZFSet → ZFSet - { x } = ( x , x ) + -- {_} : ZFSet → ZFSet + -- { x } = ( x , x ) data infinite-d : ( x : Ordinal ) → Set n where iφ : infinite-d o∅