Abstract
This chapter develops a theory of categorical normativity, of those principles that have authority over us regardless of our ends and interests. It argues that there is an intimate connection between these norms and the conditions of agency. In this respect, it offers a version of constitutivism. But the version of constitutivism defended is unique in a few respects. First, it is naturalistic: agency is an emergent property, like the properties of biology and economics. Second, it is social: agency is something constructed by the complex interaction of agents. And third, it supports the normativity of a particular contractualist procedure: adhering to Kant’s Formula of the Realm of Ends is a condition on agency, and so a categorical requirement.