constructor <;> apply Set.subset_iUnion_of_subset 0 (by simp)
α : Type u_1
inst✝⁴ : DecidableEq α
inst✝³ : Inhabited α
𝓓 : DeductionParameter α
inst✝² : 𝓓.IncludeEFQ
inst✝¹ : Inhabited α
inst✝ : Encodable α
t : Tableau α
hCon : (𝓓)-Consistent t
⊢ t ⊆ t∞
no goals