Let \(U\) be a universe. Then \(\mathord {\textnormal {\textsf {Topos}}}^{(1)}(U)\) is the initial category with \(U\)-étale morphisms, where the universal étale morphism in \(\mathord {\textnormal {\textsf {Topos}}}^{(1)}(U)\) is \(\mathord {\textnormal {\textsf {p}}}:\mathbb {A}_{\bullet }\rightarrow \mathbb {A}\) defined in [000K].