exact h₂.right $ le_trans l₄ h₁
t u : Th
p : Pr
h₁ : formalApplicationFunction t u ≤ ↑p
Δ : Set Form := { f | ¬formalApplication (↑t) (▲{f}) ⊆ ↑↑p }
P : Form
h₂ : P ∈ ↑u ∩ Δ
l₃ : ▲{P} ⊆ ↑u
l₄ : formalApplication (↑t) (▲{P}) ≤ formalApplication ↑t ↑u
⊢ False
no goals