This chapter extends and clarifies the Kantian intuitionist view that a qualified Rossian intuitionism can be integrated with a version of Kant's humanity formula. In doing this, it briefly sketches Kantian intuitionism; it explicates the notion of treatment of persons — whether merely as means or as ends in themselves — as kinds of conduct in a sense the chapter explicates; and it introduces a distinction between thick and thin ethical questions. Thin ethical questions concern act-types, understood one-dimensionally; thick ethical questions concern conduct-types, which are three-dimensional. The theoretical framework provided by the chapter clarifies the way in which an understanding of the obligations expressed in the humanity formula bea...