Theorem: FOL.NV.Sub.Var.All.Rec.substitution_theorem_aux
Proof state before:
case h
D : Type
I : Interpretation D
head✝ : Definition
tail✝ : List Definition
tail_ih✝ :
  ∀ (V V' : VarAssignment D) (σ σ' : VarName → VarName) (binders : Finset VarName) (F : Formula),
    admitsAux σ binders F →
      (∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)) →
        (∀ v ∈ binders, v = σ' v) →
          (∀ v ∉ binders, σ' v = σ v) → (Holds D I V tail✝ F ↔ Holds D I V' tail✝ (fastReplaceFree σ' F))
x : VarName
phi : Formula
phi_ih :
  ∀ (V V' : VarAssignment D) (σ σ' : VarName → VarName) (binders : Finset VarName),
    admitsAux σ binders phi →
      (∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)) →
        (∀ v ∈ binders, v = σ' v) →
          (∀ v ∉ binders, σ' v = σ v) →
            (Holds D I V (head✝ :: tail✝) phi ↔ Holds D I V' (head✝ :: tail✝) (fastReplaceFree σ' phi))
V V' : VarAssignment D
σ σ' : VarName → VarName
binders : Finset VarName
h1 : admitsAux σ (binders ∪ {x}) phi
h2 : ∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)
h2' : ∀ v ∈ binders, v = σ' v
h3 : ∀ v ∉ binders, σ' v = σ v
d : D
⊢ Holds D I (Function.updateITE V x d) (head✝ :: tail✝) phi ↔
    Holds D I (Function.updateITE V' x d) (head✝ :: tail✝) (fastReplaceFree (Function.updateITE σ' x x) phi)
Tactic:
apply phi_ih (Function.updateITE V x d) (Function.updateITE V' x d) σ (Function.updateITE σ' x x) (binders ∪ {x}) h1
Proof state after:
case h.h2
D : Type
I : Interpretation D
head✝ : Definition
tail✝ : List Definition
tail_ih✝ :
  ∀ (V V' : VarAssignment D) (σ σ' : VarName → VarName) (binders : Finset VarName) (F : Formula),
    admitsAux σ binders F →
      (∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)) →
        (∀ v ∈ binders, v = σ' v) →
          (∀ v ∉ binders, σ' v = σ v) → (Holds D I V tail✝ F ↔ Holds D I V' tail✝ (fastReplaceFree σ' F))
x : VarName
phi : Formula
phi_ih :
  ∀ (V V' : VarAssignment D) (σ σ' : VarName → VarName) (binders : Finset VarName),
    admitsAux σ binders phi →
      (∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)) →
        (∀ v ∈ binders, v = σ' v) →
          (∀ v ∉ binders, σ' v = σ v) →
            (Holds D I V (head✝ :: tail✝) phi ↔ Holds D I V' (head✝ :: tail✝) (fastReplaceFree σ' phi))
V V' : VarAssignment D
σ σ' : VarName → VarName
binders : Finset VarName
h1 : admitsAux σ (binders ∪ {x}) phi
h2 : ∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)
h2' : ∀ v ∈ binders, v = σ' v
h3 : ∀ v ∉ binders, σ' v = σ v
d : D
⊢ ∀ (v : VarName),
    v ∈ binders ∪ {x} ∨ Function.updateITE σ' x x v ∉ binders ∪ {x} →
      Function.updateITE V x d v = Function.updateITE V' x d (Function.updateITE σ' x x v)

case h.h2'
D : Type
I : Interpretation D
head✝ : Definition
tail✝ : List Definition
tail_ih✝ :
  ∀ (V V' : VarAssignment D) (σ σ' : VarName → VarName) (binders : Finset VarName) (F : Formula),
    admitsAux σ binders F →
      (∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)) →
        (∀ v ∈ binders, v = σ' v) →
          (∀ v ∉ binders, σ' v = σ v) → (Holds D I V tail✝ F ↔ Holds D I V' tail✝ (fastReplaceFree σ' F))
x : VarName
phi : Formula
phi_ih :
  ∀ (V V' : VarAssignment D) (σ σ' : VarName → VarName) (binders : Finset VarName),
    admitsAux σ binders phi →
      (∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)) →
        (∀ v ∈ binders, v = σ' v) →
          (∀ v ∉ binders, σ' v = σ v) →
            (Holds D I V (head✝ :: tail✝) phi ↔ Holds D I V' (head✝ :: tail✝) (fastReplaceFree σ' phi))
V V' : VarAssignment D
σ σ' : VarName → VarName
binders : Finset VarName
h1 : admitsAux σ (binders ∪ {x}) phi
h2 : ∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)
h2' : ∀ v ∈ binders, v = σ' v
h3 : ∀ v ∉ binders, σ' v = σ v
d : D
⊢ ∀ v ∈ binders ∪ {x}, v = Function.updateITE σ' x x v

case h.h3
D : Type
I : Interpretation D
head✝ : Definition
tail✝ : List Definition
tail_ih✝ :
  ∀ (V V' : VarAssignment D) (σ σ' : VarName → VarName) (binders : Finset VarName) (F : Formula),
    admitsAux σ binders F →
      (∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)) →
        (∀ v ∈ binders, v = σ' v) →
          (∀ v ∉ binders, σ' v = σ v) → (Holds D I V tail✝ F ↔ Holds D I V' tail✝ (fastReplaceFree σ' F))
x : VarName
phi : Formula
phi_ih :
  ∀ (V V' : VarAssignment D) (σ σ' : VarName → VarName) (binders : Finset VarName),
    admitsAux σ binders phi →
      (∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)) →
        (∀ v ∈ binders, v = σ' v) →
          (∀ v ∉ binders, σ' v = σ v) →
            (Holds D I V (head✝ :: tail✝) phi ↔ Holds D I V' (head✝ :: tail✝) (fastReplaceFree σ' phi))
V V' : VarAssignment D
σ σ' : VarName → VarName
binders : Finset VarName
h1 : admitsAux σ (binders ∪ {x}) phi
h2 : ∀ (v : VarName), v ∈ binders ∨ σ' v ∉ binders → V v = V' (σ' v)
h2' : ∀ v ∈ binders, v = σ' v
h3 : ∀ v ∉ binders, σ' v = σ v
d : D
⊢ ∀ v ∉ binders ∪ {x}, Function.updateITE σ' x x v = σ v