Abstract
Kantian constructivists locate the source of normativity in the rational nature of valuing agents. Some further argue that accepting this premise thereby commits one to accepting the intrinsic or unconditioned value of rational nature itself. Whereas much of the critical literature on this “regress on conditions” argument has focused either on the cogency of the inference from the value-conferring capacity of the will to the unconditional value of that capacity itself or on the plausibility of the initial constructivist premise, my aim is to press the argument from a different direction by asking just how Kantian the constructivist needs to be in order to support a regress on conditions argument. Specifically, I maintain that the argument succeeds only given a full-fledged Kantian moral psychology, including a presupposition of transcendental freedom. If correct, this could have implications regarding the compatibility of Kantian ethics and philosophic naturalism