have := hbar (lit, _) (by assumption)
case intro.inr
maxLit : Nat
c : Clause Nat
lit : Nat
left✝ : ∃ a, a ∈ c ∧ a.fst = maxLit
hbar : ∀ (a : Nat × Bool), a ∈ c → a.fst ≤ maxLit
h✝ : (lit, true) ∈ c
⊢ lit ≤ maxLit
case intro.inr
maxLit : Nat
c : Clause Nat
lit : Nat
left✝ : ∃ a, a ∈ c ∧ a.fst = maxLit
hbar : ∀ (a : Nat × Bool), a ∈ c → a.fst ≤ maxLit
h✝ : (lit, true) ∈ c
this : (lit, true).fst ≤ maxLit
⊢ lit ≤ maxLit