simp [flat_iff_cl_self, diff_eq_empty.2 hIE, inter_assoc, inter_eq_self_of_subset_right hIE]
α : Type u_1
M : Matroid α
I✝ F X Y F' F₀ F₁ F₂ P L H H₁ H₂ H' B C K : Set α
e f : α
I E : Set α
hIE : I ⊆ E
⊢ (uniqueBaseOn E I).Flat F ↔ F ⊆ I
no goals