new E → ((D ∨ A → D) → (C → ((F → D) → (C ∧ B → (C → (((F → B) → C) → G ∨ ((D ∨ E) ∨ (F ∨ C))))))))
intro
intro
intro
intro
intro
cases 4
intro
intro
cases 4
right
left
right
exact 0