 Borel, like Poincaré, adheres to a point of view—definability in finitely many words—which is an extension of the algebraic, Kroneckerian point of view: only objects constructible in finitely many steps are proper mathematical objects. However, unlike Poincaré, he disregards the problem of predicative definitions: for him all paradoxes of set theory derive from viewing the proposition that every denumerable set is effectively enumerable (“Tout ensemble dénombrable est effectivement énumérable”) as evident, which is false.