exact l₄ ⟨Q,h₂,⟨BProof.ax rfl⟩⟩
t u : Th
p : Pr
h₁✝ : formalApplicationFunction t u ≤ ↑p
Δ : Set Form := { f | ¬formalApplication (▲{f}) ↑u ⊆ ↑↑p }
l₄✝ : lindenbaumExtension t Δ ∩ Δ = ∅
P : Form
h₁ : P ∈ formalApplication (lindenbaumExtension t Δ) ↑u
Q : Form
h₂ : Q ∈ ↑u
h₃ : Q⊃P ∈ lindenbaumExtension t Δ
l₄ : formalApplication (▲{Q⊃P}) ↑u ⊆ ↑↑p
⊢ P ∈ ↑↑p
no goals