changeset 674:a48845e246e4

...
author Shinji KONO <kono@ie.u-ryukyu.ac.jp>
date Sat, 09 Jul 2022 11:16:57 +0900
parents 79616ba278c0
children 6a9a98904f7a
files src/OrdUtil.agda src/zorn.agda
diffstat 2 files changed, 102 insertions(+), 115 deletions(-) [+]
line wrap: on
line diff
--- a/src/OrdUtil.agda	Fri Jul 08 17:42:29 2022 +0900
+++ b/src/OrdUtil.agda	Sat Jul 09 11:16:57 2022 +0900
@@ -167,6 +167,12 @@
 o≤-refl :  { i : Ordinal } → i o≤ i
 o≤-refl {i} = subst (λ k → i o< osuc k ) refl <-osuc
 
+o≤? : (x y : Ordinal) → Dec ( x o≤ y )
+o≤? x y with trio< x y
+... | tri< a ¬b ¬c = yes (ordtrans a <-osuc)
+... | tri≈ ¬a b ¬c = yes (o≤-refl0 b)
+... | tri> ¬a ¬b c = no (λ n → osuc-< n c )
+
 OrdTrans :  Transitive  _o≤_
 OrdTrans a≤b b≤c with osuc-≡< a≤b | osuc-≡< b≤c
 OrdTrans a≤b b≤c | case1 refl | case1 refl = <-osuc
--- a/src/zorn.agda	Fri Jul 08 17:42:29 2022 +0900
+++ b/src/zorn.agda	Sat Jul 09 11:16:57 2022 +0900
@@ -262,17 +262,20 @@
    field
       psup :  Ordinal
       p≤z : psup o≤ z 
-      pchain : {px : Ordinal} → px o≤ z → (w : Ordinal) →  Chain A f mf ay px w
-      chain-mono : (px : Ordinal) → (x≤p : px o≤ psup ) → (w : Ordinal ) →  Chain A f mf ay px w → Chain A f mf ay psup w 
+      chainf : {px : Ordinal} → px o≤ z → (w : Ordinal) →  Chain A f mf ay px w
+      chain-mono1 : (px : Ordinal) → (x≤p : px o≤ psup ) → (w : Ordinal ) →  Chain A f mf ay px w → Chain A f mf ay psup w 
 
 ChainF : (A : HOD) →  ( f : Ordinal → Ordinal )  (mf : ≤-monotonic-f A f) {y : Ordinal} (ay : odef A y) 
      → (z : Ordinal) →  ZChain1 A f mf ay (& A) →  HOD
 ChainF A f mf {y} ay z zc = record { od = record { def = λ x → odef A x ∧ Chain A f mf ay (ZChain1.psup zc) x } ; odmax = & A ; <odmax =  λ {y} sy → ∈∧P→o< sy } 
 
-record ZChain ( A : HOD )    ( f : Ordinal → Ordinal )  (mf : ≤-monotonic-f A f) {init : Ordinal} (ay : odef A init)  (zc0 :  ZChain1 A f mf ay (& A) ) ( z : Ordinal ) : Set (Level.suc n) where
+record ZChain ( A : HOD )    ( f : Ordinal → Ordinal )  (mf : ≤-monotonic-f A f) {init : Ordinal} (ay : odef A init)  
+          (zc0 : (x : Ordinal) →  ZChain1 A f mf ay x ) ( z : Ordinal ) : Set (Level.suc n) where
    chain : HOD
-   chain = ChainF A f mf ay z zc0
+   chain = ChainF A f mf ay z (zc0 (& A))
    field
+      chain-mono : (px py : Ordinal) → (px≤py : px o≤ py ) (y≤x : py o≤ z ) → (w : Ordinal ) 
+          → Chain A f mf ay (ZChain1.psup (zc0 (& A))) px → Chain A f mf ay (ZChain1.psup (zc0 (& A))) py
       chain⊆A : chain ⊆' A
       chain∋init : odef chain init
       initial : {y : Ordinal } → odef chain y → * init ≤ * y
@@ -345,7 +348,7 @@
      cf-is-≤-monotonic : (nmx : ¬ Maximal A ) →  ≤-monotonic-f A ( cf nmx )
      cf-is-≤-monotonic nmx x ax = ⟪ case2 (proj1 ( cf-is-<-monotonic nmx x ax  ))  , proj2 ( cf-is-<-monotonic nmx x ax  ) ⟫
 
-     sp0 : ( f : Ordinal → Ordinal ) → (mf : ≤-monotonic-f A f ) (zc0 : ZChain1 A f mf as0 (& A) ) (zc : ZChain A f mf as0 zc0 (& A) ) 
+     sp0 : ( f : Ordinal → Ordinal ) → (mf : ≤-monotonic-f A f ) (zc0 : (x : Ordinal) → ZChain1 A f mf as0 x ) (zc : ZChain A f mf as0 zc0 (& A) ) 
         (total : IsTotalOrderSet (ZChain.chain zc) )  → SUP A (ZChain.chain zc)
      sp0 f mf zc0 zc total = supP (ZChain.chain zc) (ZChain.chain⊆A zc) total 
      zc< : {x y z : Ordinal} → {P : Set n} → (x o< y → P) → x o< z → z o< y → P
@@ -354,7 +357,7 @@
      ---
      --- the maximum chain  has fix point of any ≤-monotonic function
      ---
-     fixpoint :  ( f : Ordinal → Ordinal ) → (mf : ≤-monotonic-f A f ) (zc0 : ZChain1 A f mf as0 (& A)) (zc : ZChain A f mf as0 zc0 (& A) )
+     fixpoint :  ( f : Ordinal → Ordinal ) → (mf : ≤-monotonic-f A f ) (zc0 : (x : Ordinal) → ZChain1 A f mf as0 x) (zc : ZChain A f mf as0 zc0 (& A) )
             → (total : IsTotalOrderSet (ZChain.chain zc) )
             → f (& (SUP.sup (sp0 f mf zc0 zc total ))) ≡ & (SUP.sup (sp0 f mf zc0 zc  total))
      fixpoint f mf zc0 zc total = z14 where
@@ -403,7 +406,7 @@
      -- ZChain forces fix point on any ≤-monotonic function (fixpoint)
      -- ¬ Maximal create cf which is a <-monotonic function by axiom of choice. This contradicts fix point of ZChain
      --
-     z04 :  (nmx : ¬ Maximal A ) → (zc0 : ZChain1 A (cf nmx) (cf-is-≤-monotonic nmx)  as0 (& A)) (zc : ZChain A (cf nmx) (cf-is-≤-monotonic nmx) as0 zc0 (& A)) 
+     z04 :  (nmx : ¬ Maximal A ) → (zc0 : (x : Ordinal) → ZChain1 A (cf nmx) (cf-is-≤-monotonic nmx)  as0 x) (zc : ZChain A (cf nmx) (cf-is-≤-monotonic nmx) as0 zc0 (& A)) 
            → IsTotalOrderSet (ZChain.chain zc) → ⊥
      z04 nmx zc0 zc total = <-irr0  {* (cf nmx c)} {* c} (subst (λ k → odef A k ) (sym &iso) (proj1 (is-cf nmx (SUP.A∋maximal  sp1 ))))
                                                (subst (λ k → odef A (& k)) (sym *iso) (SUP.A∋maximal sp1) )
@@ -464,46 +467,59 @@
           ... | case1 is-sup = ?
           ... | case2 ¬x=sup = ?
 
-     ind : ( f : Ordinal → Ordinal ) → (mf : ≤-monotonic-f A f ) {y : Ordinal} (ay : odef A y) → (x : Ordinal) → (zc0 :  ZChain1 A f mf ay (& A)) 
+     ind : ( f : Ordinal → Ordinal ) → (mf : ≤-monotonic-f A f ) {y : Ordinal} (ay : odef A y) → (x : Ordinal) 
+         → (zc0 : (x : Ordinal) →  ZChain1 A f mf ay x) 
          → ((z : Ordinal) → z o< x → ZChain A f mf ay zc0 z) → ZChain A f mf ay zc0 x
-     ind f mf {y} ay x zc0 prev with Oprev-p x
-     ... | yes op = zc4 where
-          --
-          -- we have previous ordinal to use induction
-          --
-          px = Oprev.oprev op
-          supf : Ordinal → HOD
-          supf x = ? -- ZChain1.chain zc0 
-          zc : ZChain A f mf ay zc0 (Oprev.oprev op)
-          zc = prev px (subst (λ k → px o< k) (Oprev.oprev=x op) <-osuc ) 
-          zc-b<x : (b : Ordinal ) → b o< x → b o< osuc px
-          zc-b<x b lt = subst (λ k → b o< k ) (sym (Oprev.oprev=x op)) lt 
-          px<x : px o< x
-          px<x = subst (λ k → px o< k) (Oprev.oprev=x op) <-osuc
+     ind f mf {y} ay x zc0 prev = zc4 where
+          zc : {z1 : Ordinal} → z1 o< x → ZChain A f mf ay zc0 z1
+          zc z1 with Oprev-p x
+          ... | yes op = ? where
+              --
+              -- we have previous ordinal to use induction
+              --
+              px = Oprev.oprev op
+              supf : Ordinal → HOD
+              supf x =  ChainF A f mf ay x (zc0 (& A))
+              -- zc : ZChain A f mf ay zc0 (Oprev.oprev op)
+              -- zc = prev px (subst (λ k → px o< k) (Oprev.oprev=x op) <-osuc ) 
+              px<x : px o< x
+              px<x = subst (λ k → px o< k) (Oprev.oprev=x op) <-osuc
+          ... | no ¬ox = ? where
+             supf : Ordinal → HOD
+             supf x = ? -- Z?Chain1.chain zc0 
+             uzc : {z : Ordinal} → (u : UChain x {!!} z) → ZChain A f mf ay zc0 (UChain.u u)
+             uzc {z} u =  prev (UChain.u u) (UChain.u<x u) 
+             Uz : HOD
+             Uz = record { od = record { def = λ z → odef A z ∧ ( UChain z {!!} x ∨ FClosure A f y z ) } ; odmax = & A ; <odmax = {!!}  }
 
           -- if previous chain satisfies maximality, we caan reuse it
           --
-          no-extenion : ( {a b : Ordinal} → odef (ZChain.chain zc) a → b o< osuc x → (ab : odef A b) →
-                    HasPrev A (ZChain.chain zc) ab f ∨  IsSup A (ZChain.chain zc) ab →
-                            * a < * b → odef (ZChain.chain zc) b ) → ZChain A f mf ay {!!}  x
-          no-extenion is-max = record { chain⊆A = {!!} -- subst (λ k → k ⊆' A ) {!!} (ZChain.chain⊆A zc)
-                     ; initial = subst (λ k →  {y₁ : Ordinal} → odef k y₁ → * y ≤ * y₁ ) {!!} (ZChain.initial zc)
-                     ; f-next =  subst (λ k → {a : Ordinal} → odef k a → odef k (f a) ) {!!} (ZChain.f-next zc) 
-                     ; f-total = {!!} 
-                     ; chain∋init  = subst (λ k → odef k y ) {!!} (ZChain.chain∋init  zc) 
-                     ; is-max = subst (λ k → {a b : Ordinal} → odef k a → b o< osuc x → (ab : odef A b) →
-                                 HasPrev A k ab f ∨  IsSup A k ab → * a < * b → odef k b  ) {!!} is-max } where
+          no-extenion : ( {a b : Ordinal} → odef (ZChain.chain (zc ? )) a → b o< osuc x → (ab : odef A b) →
+                    HasPrev A (ZChain.chain (zc ?) ) ab f ∨  IsSup A (ZChain.chain (zc ?) ) ab →
+                            * a < * b → odef (ZChain.chain (zc ?) ) b ) → ZChain A f mf ay zc0 x
+          no-extenion is-max with o≤? x (& A)
+          ... | no n = ? where
+          ... | yes x≤a with ZChain1.chainf (zc0 (& A)) x≤a x
+          ... | ch-init _ _  x=0 fc = ?
+          ... | ch-is-sup ax is-sup fc = ? where
+          -- = record { chain⊆A = {!!} -- subst (λ k → k ⊆' A ) {!!} (ZChain.chain⊆A zc)
+          --           ; initial = subst (λ k →  {y₁ : Ordinal} → odef k y₁ → * y ≤ * y₁ ) {!!} (ZChain.initial zc)
+          --           ; f-next =  subst (λ k → {a : Ordinal} → odef k a → odef k (f a) ) {!!} (ZChain.f-next zc) 
+          --           ; f-total = {!!} 
+          --           ; chain∋init  = subst (λ k → odef k y ) {!!} (ZChain.chain∋init  zc) 
+          --           ; is-max = subst (λ k → {a b : Ordinal} → odef k a → b o< osuc x → (ab : odef A b) →
+          --                       HasPrev A k ab f ∨  IsSup A k ab → * a < * b → odef k b  ) {!!} is-max } where
                 supf0 : Ordinal → HOD
                 supf0 z with trio< z x
-                ... | tri< a ¬b ¬c = supf z
-                ... | tri≈ ¬a b ¬c = ZChain.chain zc
-                ... | tri> ¬a ¬b c = ZChain.chain zc 
-                seq : ZChain.chain zc ≡ supf0 x 
+                ... | tri< a ¬b ¬c = ?
+                ... | tri≈ ¬a b ¬c = ZChain.chain (zc ?)
+                ... | tri> ¬a ¬b c = ZChain.chain (zc ?)
+                seq : ZChain.chain (zc ?) ≡ supf0 x 
                 seq with trio< x x
                 ... | tri< a ¬b ¬c = ⊥-elim ( ¬b refl )
                 ... | tri≈ ¬a b ¬c = refl 
                 ... | tri> ¬a ¬b c = refl 
-                seq<x : {b : Ordinal } → b o< x →  supf b  ≡ supf0 b
+                seq<x : {b : Ordinal } → b o< x →  ? -- supf b  ≡ supf0 b
                 seq<x {b} b<x with trio< b x
                 ... | tri< a ¬b ¬c = refl
                 ... | tri≈ ¬a b₁ ¬c = ⊥-elim (¬a  b<x )
@@ -512,28 +528,29 @@
           zc4 : ZChain A f mf ay zc0 x 
           zc4 with ODC.∋-p O A (* x)
           ... | no noax = no-extenion zc1  where -- ¬ A ∋ p, just skip
-                zc1 : {a b : Ordinal} → odef (ZChain.chain zc) a → b o< osuc x → (ab : odef A b) →
-                    HasPrev A (ZChain.chain zc) ab f ∨  IsSup A (ZChain.chain zc) ab →
-                            * a < * b → odef (ZChain.chain zc) b
+                zc1 : {a b : Ordinal} → odef (ZChain.chain (zc ?) ) a → b o< osuc x → (ab : odef A b) →
+                    HasPrev A (ZChain.chain (zc ?) ) ab f ∨  IsSup A (ZChain.chain (zc ?) ) ab →
+                            * a < * b → odef (ZChain.chain (zc ?) ) b
                 zc1 {a} {b} za b<ox ab P a<b with osuc-≡< b<ox
                 ... | case1 eq = ⊥-elim ( noax (subst (λ k → odef A k) (trans eq (sym &iso)) ab ) )
-                ... | case2 lt = ZChain.is-max zc za (zc-b<x b lt)  ab P a<b
-          ... | yes ax with ODC.p∨¬p O ( HasPrev A (ZChain.chain zc) ax f )   -- we have to check adding x preserve is-max ZChain A y f mf zc0 x
+                ... | case2 lt = ZChain.is-max (zc ?) za ?  ab P a<b
+          ... | yes ax with ODC.p∨¬p O ( HasPrev A (ZChain.chain (zc ?) ) ax f )   
+               -- we have to check adding x preserve is-max ZChain A y f mf zc0 x
           ... | case1 pr = no-extenion zc7  where -- we have previous A ∋ z < x , f z ≡ x, so chain ∋ f z ≡ x because of f-next
-                chain0 = ZChain.chain zc
-                zc7 :  {a b : Ordinal} → odef (ZChain.chain zc) a → b o< osuc x → (ab : odef A b) →
-                            HasPrev A (ZChain.chain zc) ab f ∨ IsSup A (ZChain.chain zc) ab →
-                            * a < * b → odef (ZChain.chain zc) b
+                chain0 = ZChain.chain (zc ?) 
+                zc7 :  {a b : Ordinal} → odef (ZChain.chain (zc ?) ) a → b o< osuc x → (ab : odef A b) →
+                            HasPrev A (ZChain.chain (zc ?) ) ab f ∨ IsSup A (ZChain.chain (zc ?) ) ab →
+                            * a < * b → odef (ZChain.chain (zc ?) ) b
                 zc7 {a} {b} za b<ox ab P a<b with osuc-≡< b<ox
-                ... | case2 lt = ZChain.is-max zc za (zc-b<x b lt) ab P a<b
-                ... | case1 b=x = subst (λ k → odef chain0 k ) (trans (sym (HasPrev.x=fy pr )) (trans &iso (sym b=x)) ) ( ZChain.f-next zc (HasPrev.ay pr))
-          ... | case2 ¬fy<x with ODC.p∨¬p O (IsSup A (ZChain.chain zc) ax )
-          ... | case1 is-sup = -- x is a sup of zc 
+                ... | case2 lt = ZChain.is-max (zc ?) za ? ab P a<b
+                ... | case1 b=x = subst (λ k → odef chain0 k ) (trans (sym (HasPrev.x=fy pr )) (trans &iso (sym b=x)) ) ( ZChain.f-next (zc ?) (HasPrev.ay pr))
+          ... | case2 ¬fy<x with ODC.p∨¬p O (IsSup A (ZChain.chain (zc ?) ) ax )
+          ... | case1 is-sup = -- x is a sup of (zc ?) 
                 record {  chain⊆A = {!!} ; f-next = {!!}  ; f-total = {!!}
                      ; initial = {!!} ; chain∋init  = {!!} ; is-max = {!!}   } where
-                sup0 : SUP A (ZChain.chain zc) 
+                sup0 : SUP A (ZChain.chain (zc ?) ) 
                 sup0 = record { sup = * x ; A∋maximal = ax ; x<sup = x21 } where
-                        x21 :  {y : HOD} → ZChain.chain zc ∋ y → (y ≡ * x) ∨ (y < * x)
+                        x21 :  {y : HOD} → ZChain.chain (zc ?) ∋ y → (y ≡ * x) ∨ (y < * x)
                         x21 {y} zy with IsSup.x<sup is-sup zy 
                         ... | case1 y=x = case1 ( subst₂ (λ j k → j ≡ * k  ) *iso &iso ( cong (*) y=x)  )
                         ... | case2 y<x = case2 (subst₂ (λ j k → j < * k ) *iso &iso y<x  )
@@ -541,22 +558,22 @@
                 sp = SUP.sup sup0 
                 x=sup : x ≡ & sp 
                 x=sup = sym &iso 
-                chain0 = ZChain.chain zc
+                chain0 = ZChain.chain (zc ?) 
                 sc<A : {y : Ordinal} → odef chain0 y ∨ FClosure A f (& sp) y → y o< & A
-                sc<A {y} (case1 zx) = subst (λ k → k o< (& A)) &iso ( c<→o< (ZChain.chain⊆A zc (subst (λ k → odef chain0 k) (sym &iso) zx )))
+                sc<A {y} (case1 zx) = subst (λ k → k o< (& A)) &iso ( c<→o< (ZChain.chain⊆A (zc ?) (subst (λ k → odef chain0 k) (sym &iso) zx )))
                 sc<A {y} (case2 fx) = subst (λ k → k o< (& A)) &iso ( c<→o< (subst (λ k → odef A k ) (sym &iso) (A∋fc (& sp) f mf fx )) )
                 schain : HOD
                 schain = record { od = record { def = λ x → odef chain0 x ∨ (FClosure A f (& sp) x) } ; odmax = & A ; <odmax = λ {y} sy → sc<A {y} sy  }
                 supf0 : Ordinal → HOD
                 supf0 z with trio< z x
-                ... | tri< a ¬b ¬c = supf z
+                ... | tri< a ¬b ¬c = ? -- supf z
                 ... | tri≈ ¬a b ¬c = schain 
                 ... | tri> ¬a ¬b c = schain
                 A∋schain : {x : HOD } → schain ∋ x → A ∋ x
-                A∋schain (case1 zx ) = ZChain.chain⊆A zc zx 
+                A∋schain (case1 zx ) = ZChain.chain⊆A (zc ?) zx 
                 A∋schain {y} (case2 fx ) = A∋fc (& sp) f mf fx 
                 s⊆A : schain ⊆' A
-                s⊆A {x} (case1 zx) = ZChain.chain⊆A zc zx
+                s⊆A {x} (case1 zx) = ZChain.chain⊆A (zc ?) zx
                 s⊆A {x} (case2 fx) = A∋fc (& sp) f mf fx 
                 cmp  : {a b : HOD} (za : odef chain0 (& a)) (fb : FClosure A f (& sp) (& b)) → Tri (a < b) (a ≡ b) (b < a )
                 cmp {a} {b} za fb  with SUP.x<sup sup0 za | s≤fc (& sp) f mf fb  
@@ -573,7 +590,7 @@
                         a<b : a < b
                         a<b = ptrans  (subst (λ k → a < k ) (sym *iso) a<sp ) ( subst₂ (λ j k → j < k ) refl *iso sp<b )
                 scmp : {a b : HOD} → odef schain (& a) → odef schain (& b) → Tri (a < b) (a ≡ b) (b < a )
-                scmp {a} {b} (case1 za) (case1 zb) = {!!} -- ZChain.f-total zc {px} {px} o≤-refl za zb
+                scmp {a} {b} (case1 za) (case1 zb) = {!!} -- ZChain.f-total (zc ?) {px} {px} o≤-refl za zb
                 scmp {a} {b} (case1 za) (case2 fb) = cmp za fb 
                 scmp  (case2 fa) (case1 zb) with  cmp zb fa
                 ... | tri< a ¬b ¬c = tri> ¬c (λ eq → ¬b (sym eq))  a
@@ -581,17 +598,17 @@
                 ... | tri> ¬a ¬b c = tri< c (λ eq → ¬b (sym eq))  ¬a
                 scmp (case2 fa) (case2 fb) = subst₂ (λ a b → Tri (a < b) (a ≡ b) (b < a ) ) *iso *iso (fcn-cmp (& sp) f mf fa fb)
                 scnext : {a : Ordinal} → odef schain a → odef schain (f a)
-                scnext {x} (case1 zx) = case1 (ZChain.f-next zc zx)
+                scnext {x} (case1 zx) = case1 (ZChain.f-next (zc ?) zx)
                 scnext {x} (case2 sx) = case2 ( fsuc x sx )
                 scinit :  {x : Ordinal} → odef schain x → * y ≤ * x
-                scinit {x} (case1 zx) = ZChain.initial zc zx
-                scinit {x} (case2 sx) with  (s≤fc (& sp) f mf sx ) |  SUP.x<sup sup0 (subst (λ k → odef chain0 k ) (sym &iso) ( ZChain.chain∋init zc ) )
+                scinit {x} (case1 zx) = ZChain.initial (zc ?) zx
+                scinit {x} (case2 sx) with  (s≤fc (& sp) f mf sx ) |  SUP.x<sup sup0 (subst (λ k → odef chain0 k ) (sym &iso) ( ZChain.chain∋init (zc ?) ) )
                 ... | case1 sp=x | case1 y=sp = case1 (trans y=sp (subst (λ k → k ≡ * x ) *iso sp=x ) )
                 ... | case1 sp=x | case2 y<sp = case2 (subst (λ k → * y < k ) (trans (sym *iso) sp=x) y<sp )
                 ... | case2 sp<x | case1 y=sp = case2 (subst (λ k → k < * x ) (trans *iso (sym y=sp )) sp<x )
                 ... | case2 sp<x | case2 y<sp = case2 (ptrans y<sp (subst (λ k → k < * x ) *iso sp<x) )
                 A∋za : {a : Ordinal } → odef chain0 a → odef A a
-                A∋za za = ZChain.chain⊆A zc za 
+                A∋za za = ZChain.chain⊆A (zc ?) za 
                 za<sup :  {a : Ordinal } → odef chain0 a → ( * a ≡ sp ) ∨  ( * a < sp )
                 za<sup za =  SUP.x<sup sup0 (subst (λ k → odef chain0 k ) (sym &iso) za )
                 s-ismax : {a b : Ordinal} → odef schain a → b o< osuc x → (ab : odef A b)
@@ -602,84 +619,48 @@
                 s-ismax {a} {b} (case1 za) b<ox ab (case1 p) a<b | case2 b<x = z21 p where   -- has previous
                      z21 : HasPrev A schain ab f → odef schain b
                      z21 record { y = y ; ay = (case1 zy) ; x=fy = x=fy } = 
-                           case1 (ZChain.is-max zc za (zc-b<x b b<x) ab (case1 record { y = y ; ay = zy ; x=fy = x=fy }) a<b )
+                           case1 (ZChain.is-max (zc ?) za ? ab (case1 record { y = y ; ay = zy ; x=fy = x=fy }) a<b )
                      z21 record { y = y ; ay = (case2 sy) ; x=fy = x=fy } = subst (λ k → odef schain k) (sym x=fy) (case2 (fsuc y sy) )
-                s-ismax {a} {b} (case1 za) b<ox ab (case2 p) a<b | case2 b<x = case1 (ZChain.is-max zc za (zc-b<x b b<x) ab (case2 z22) a<b ) where -- previous sup
-                     z22 : IsSup A (ZChain.chain zc)   ab 
+                s-ismax {a} {b} (case1 za) b<ox ab (case2 p) a<b | case2 b<x = case1 (ZChain.is-max (zc ?) za ? ab (case2 z22) a<b ) where -- previous sup
+                     z22 : IsSup A (ZChain.chain (zc ?) )   ab 
                      z22 = record { x<sup = λ {y} zy → IsSup.x<sup p (case1 zy ) }
                 s-ismax {a} {b} (case2 sa) b<ox ab (case1 p)  a<b | case2 b<x with HasPrev.ay p
-                ... | case1 zy = case1 (subst (λ k → odef chain0 k ) (sym (HasPrev.x=fy p)) (ZChain.f-next zc zy ))               -- in previous closure of f
+                ... | case1 zy = case1 (subst (λ k → odef chain0 k ) (sym (HasPrev.x=fy p)) (ZChain.f-next (zc ?) zy ))               -- in previous closure of f
                 ... | case2 sy = case2 (subst (λ k → FClosure A f (& (* x)) k ) (sym (HasPrev.x=fy p)) (fsuc (HasPrev.y p) sy ))  -- in current  closure of f
                 s-ismax {a} {b} (case2 sa) b<ox ab (case2 p)  a<b | case2 b<x = case1 z23 where -- sup o< x is already in zc
-                     z24 : IsSup A schain ab → IsSup A (ZChain.chain zc) ab 
+                     z24 : IsSup A schain ab → IsSup A (ZChain.chain (zc ?) ) ab 
                      z24 p = record { x<sup = λ {y} zy → IsSup.x<sup p (case1 zy ) }
                      z23 : odef chain0 b
-                     z23 with IsSup.x<sup (z24 p) ( ZChain.chain∋init zc )
-                     ... | case1 y=b  = subst (λ k → odef chain0 k )  y=b ( ZChain.chain∋init zc )
-                     ... | case2 y<b  = ZChain.is-max zc (ZChain.chain∋init zc ) (zc-b<x b b<x) ab (case2 (z24 p)) y<b
+                     z23 with IsSup.x<sup (z24 p) ( ZChain.chain∋init (zc ?) )
+                     ... | case1 y=b  = subst (λ k → odef chain0 k )  y=b ( ZChain.chain∋init (zc ?) )
+                     ... | case2 y<b  = ZChain.is-max (zc ?) (ZChain.chain∋init (zc ?) ) ? ab (case2 (z24 p)) y<b
                 seq : schain ≡ supf0 x 
                 seq with trio< x x
                 ... | tri< a ¬b ¬c = ⊥-elim ( ¬b refl )
                 ... | tri≈ ¬a b ¬c = refl
                 ... | tri> ¬a ¬b c = refl
-                seq<x : {b : Ordinal } → b o< x →  supf b  ≡ supf0 b
+                seq<x : {b : Ordinal } → b o< x → ? --  supf b  ≡ supf0 b
                 seq<x {b} b<x with trio< b x
                 ... | tri< a ¬b ¬c = refl
                 ... | tri≈ ¬a b₁ ¬c = ⊥-elim (¬a  b<x )
                 ... | tri> ¬a ¬b c  = ⊥-elim (¬a  b<x )
 
           ... | case2 ¬x=sup =  no-extenion z18 where -- x is not f y' nor sup of former ZChain from y -- no extention
-                z18 :  {a b : Ordinal} → odef (ZChain.chain zc) a → b o< osuc x → (ab : odef A b) →
-                            HasPrev A (ZChain.chain zc) ab f ∨ IsSup A (ZChain.chain zc)   ab →
-                            * a < * b → odef (ZChain.chain zc) b
+                z18 :  {a b : Ordinal} → odef (ZChain.chain (zc ?) ) a → b o< osuc x → (ab : odef A b) →
+                            HasPrev A (ZChain.chain (zc ?) ) ab f ∨ IsSup A (ZChain.chain (zc ?) )   ab →
+                            * a < * b → odef (ZChain.chain (zc ?) ) b
                 z18 {a} {b} za b<x ab p a<b with osuc-≡< b<x
-                ... | case2 lt = ZChain.is-max zc za (zc-b<x b lt) ab p a<b 
+                ... | case2 lt = ZChain.is-max (zc ?) za ? ab p a<b 
                 ... | case1 b=x with p
                 ... | case1 pr = ⊥-elim ( ¬fy<x record {y = HasPrev.y pr ; ay = HasPrev.ay pr ; x=fy = trans (trans &iso (sym b=x) ) (HasPrev.x=fy pr ) } )
                 ... | case2 b=sup = ⊥-elim ( ¬x=sup record { 
                       x<sup = λ {y} zy → subst (λ k → (y ≡ k) ∨ (y << k)) (trans b=x (sym &iso)) (IsSup.x<sup b=sup zy)  } ) 
-     ... | no ¬ox = record { chain⊆A = {!!} ; f-next = {!!} ; f-total = {!!}
-                     ; initial = {!!} ; chain∋init  = {!!} ; is-max = {!!} }   where --- limit ordinal case
-         supf : Ordinal → HOD
-         supf x = ? -- Z?Chain1.chain zc0 
-         uzc : {z : Ordinal} → (u : UChain x {!!} z) → ZChain A f mf ay zc0 (UChain.u u)
-         uzc {z} u =  prev (UChain.u u) (UChain.u<x u) 
-         Uz : HOD
-         Uz = record { od = record { def = λ z → odef A z ∧ ( UChain z {!!} x ∨ FClosure A f y z ) } ; odmax = & A ; <odmax = {!!}  }
-         u-next : {z : Ordinal} → odef Uz z → odef Uz (f z)
-         u-next {z} = {!!}
-         -- (case1 u) = case1 record { u = UChain.u u ; u<x = UChain.u<x u ; chain∋z = ZChain.f-next ( uzc u ) (UChain.chain∋z u)  }
-         -- u-next {z} (case2 u) = case2 ( fsuc _ u )
-         u-initial :  {z : Ordinal} → odef Uz z → * y ≤ * z 
-         u-initial {z} = {!!}
-         -- (case1 u) = ZChain.initial ( uzc u )  (UChain.chain∋z u)
-         -- u-initial {z} (case2 u) = s≤fc _ f mf u
-         u-chain∋init :  odef Uz y
-         u-chain∋init = {!!} -- case2 ( init ay )
-         supf0 : Ordinal → HOD
-         supf0 z with trio< z x
-         ... | tri< a ¬b ¬c = ? -- ZChain1.chain zc0 
-         ... | tri≈ ¬a b ¬c = Uz 
-         ... | tri> ¬a ¬b c = Uz
-         u-mono :  {z : Ordinal} {w : Ordinal} → z o≤ w → w o≤ x → supf0 z ⊆' supf0 w
-         u-mono {z} {w} z≤w w≤x {i} with trio< z x | trio< w x
-         ... | s | t = {!!}
-
-         seq : Uz ≡ supf0 x
-         seq with trio< x x
-         ... | tri< a ¬b ¬c = ⊥-elim ( ¬b refl )
-         ... | tri≈ ¬a b ¬c = refl
-         ... | tri> ¬a ¬b c = refl
-         ord≤< : {x y z : Ordinal} → x o< z → z o≤ y → x o< y
-         ord≤< {x} {y} {z} x<z z≤y  with  osuc-≡< z≤y
-         ... | case1 z=y  = subst (λ k → x o< k ) z=y x<z
-         ... | case2 z<y  = ordtrans x<z z<y
          
      SZ0 : ( f : Ordinal → Ordinal ) → (mf : ≤-monotonic-f A f ) → {y : Ordinal} (ay : odef A y) → (x : Ordinal) → ZChain1 A f mf ay x
      SZ0 f mf ay x = TransFinite {λ z → ZChain1 A f mf ay z} (sind f mf ay ) x
 
-     SZ : ( f : Ordinal → Ordinal ) → (mf : ≤-monotonic-f A f ) → {y : Ordinal} (ay : odef A y) → ZChain A f mf ay (SZ0 f mf ay (& A))  (& A)
-     SZ f mf {y} ay = TransFinite {λ z → ZChain A f mf ay (SZ0 f mf ay (& A))  z  } (λ x → ind f mf ay x (SZ0 f mf ay (& A))  ) (& A)
+     SZ : ( f : Ordinal → Ordinal ) → (mf : ≤-monotonic-f A f ) → {y : Ordinal} (ay : odef A y) → ZChain A f mf ay (SZ0 f mf ay )  (& A)
+     SZ f mf {y} ay = TransFinite {λ z → ZChain A f mf ay (SZ0 f mf ay )  z  } (λ x → ind f mf ay x (SZ0 f mf ay )  ) (& A)
 
      zorn00 : Maximal A 
      zorn00 with is-o∅ ( & HasMaximal )  -- we have no Level (suc n) LEM 
@@ -691,7 +672,7 @@
          zorn01  = proj1  zorn03  
          zorn02 : {x : HOD} → A ∋ x → ¬ (ODC.minimal O HasMaximal (λ eq → not (=od∅→≡o∅ eq)) < x)
          zorn02 {x} ax m<x = proj2 zorn03 (& x) ax (subst₂ (λ j k → j < k) (sym *iso) (sym *iso) m<x )
-     ... | yes ¬Maximal = ⊥-elim ( z04 nmx (zc0 (& A)) zorn04 total ) where
+     ... | yes ¬Maximal = ⊥-elim ( z04 nmx zc0  zorn04 total ) where
          -- if we have no maximal, make ZChain, which contradict SUP condition
          nmx : ¬ Maximal A 
          nmx mx =  ∅< {HasMaximal} zc5 ( ≡o∅→=od∅  ¬Maximal ) where
@@ -699,7 +680,7 @@
               zc5 = ⟪  Maximal.A∋maximal mx , (λ y ay mx<y → Maximal.¬maximal<x mx (subst (λ k → odef A k ) (sym &iso) ay) (subst (λ k → k < * y) *iso mx<y) ) ⟫
          zc0 : (x : Ordinal) → ZChain1 A  (cf nmx) (cf-is-≤-monotonic nmx) as0 x
          zc0 x = TransFinite {λ z → ZChain1 A (cf nmx) (cf-is-≤-monotonic nmx)  as0 z} (sind (cf nmx) (cf-is-≤-monotonic nmx)  as0) x
-         zorn04 : ZChain A (cf nmx) (cf-is-≤-monotonic nmx) as0 (zc0 (& A)) (& A)
+         zorn04 : ZChain A (cf nmx) (cf-is-≤-monotonic nmx) as0 zc0 (& A)
          zorn04 = SZ (cf nmx) (cf-is-≤-monotonic nmx) (subst (λ k → odef A k ) &iso as ) 
          total : IsTotalOrderSet (ZChain.chain zorn04)
          total {a} {b} = zorn06  where