Kantian intuitionism as a framework for the justification of moral judgements

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 bear on interpreting Rossian principles and on resolving conflicts of obligation that constitute a challenge to the adequacy of intuitionist ethics as developed by Ross. The final section of the chapter formulates a set of weighting principles that enhance the scope, concreteness, and practical applicability of Kantian intuitionism as an ethical theory.