10.1 The category of sets

Recall that in \autorefcha:category-theory we defined the categoryMathworldPlanetmath 𝒮et to consist of all 0-types (in some universePlanetmathPlanetmath 𝒰) and maps between them, and observed that it is a category (not just a precategory). We consider successively the levels of structureMathworldPlanetmath which 𝒮et possesses.

Title 10.1 The category of sets