In seeking to neutralize affectivity and in requiring us to act for the right without reference to the conceptions of the good that normally attract our allegiance, some critics say, contemporary cognitivist theories of justice undercut human agency and leave justice hanging. This paper explores the merits of that charge by engaging the work of John Rawls and Jürgen Habermas. Rawls does offer an account of the sense of justice that can meet the motivational challenge, albeit not without compromising the (...) strict priority of the right over the good. Habermas objects to key elements of the Rawlsian compromise and defends a more strenuously pure proceduralism, acknowledging the motivational (if not the normative) difficulties this entails. The accommodations and the deficits found in Rawls and Habermas point to the irrepressible place that conceptions of the good and our affective attachments to them occupy within human moral psychology. This feature of moral psychology has more than merely practical significance. It affects the operation of practical reason, and on the contemporary cognitivist models of justice it is practical reason that establishes the validity of moral and political norms. Consequently, a fuller account of the moral psychology that supports just action also helps clarify the nature of norm justification. (shrink)