English
For x,y ∈ WithBot α, the duality respects the order relation when comparing their duals: x.toDual ≤ y.toDual ⇔ y ≤ x.
Русский
Дуальность сохраняет отношение порядка при сравнении их дуалей: x^{toDual} ≤ y^{toDual} ⇔ y ≤ x.
LaTeX
$$$ x^{\mathrm{toDual}} \le y^{\mathrm{toDual}} \iff y \le x. $$$$
Lean4
theorem toDual_lt_iff {x : WithBot α} {y : WithTop αᵒᵈ} : x.toDual < y ↔ WithTop.ofDual y < x := by
cases x <;> cases y <;> simp [toDual_lt]