new (F → E ∧ D) → (B ∧ J → (H ∧ J → (F → (J ∧ E → (C ∨ G → ((G → F) → (((E → H) → C) → B)))))))
intro
intro
cases 1
intro
cases 4
intro
intro
cases 8
intro
intro
intro
cases 1
cases 4
cases 8
exact 2