English
There is no way to view all small types as a small type; Type max(u,v) is not small.
Русский
Нельзя представить множество всех малых типов как малый тип; Type(max(u,v)) не мал.
LaTeX
$$$\neg Small(\mathrm{Type}(\max(u,v))).$$$
Lean4
theorem not_small_type : ¬Small.{u} (Type max u v)
| ⟨⟨S, ⟨e⟩⟩⟩ =>
@Function.cantor_injective (Σ α, e.symm α) (fun a => ⟨_, cast (e.3 _).symm a⟩) fun a b e =>
by
dsimp at e
injection e with h₁ h₂
simpa using h₂