intro rhs
case cons.mpr
W : Type
M : KripkeModel W
w : W
N : ℕ
X : List Formula
XS : List (List Formula)
IH : Evaluate (M, w) (discon XS) ↔ ∃ Y ∈ XS, ∀ f ∈ Y, Evaluate (M, w) f
⊢ (∃ Y ∈ X :: XS, ∀ f ∈ Y, Evaluate (M, w) f) → Evaluate (M, w) (bigCon X) ∨ ∃ Y ∈ XS, ∀ f ∈ Y, Evaluate (M, w) f
case cons.mpr
W : Type
M : KripkeModel W
w : W
N : ℕ
X : List Formula
XS : List (List Formula)
IH : Evaluate (M, w) (discon XS) ↔ ∃ Y ∈ XS, ∀ f ∈ Y, Evaluate (M, w) f
rhs : ∃ Y ∈ X :: XS, ∀ f ∈ Y, Evaluate (M, w) f
⊢ Evaluate (M, w) (bigCon X) ∨ ∃ Y ∈ XS, ∀ f ∈ Y, Evaluate (M, w) f