The paper addresses O'Neill's view that her version of Kant's Categorical Imperative, namely, the requirement of followability (RF), marks the supreme principle of reason; it takes issue with her claim that RF commits us to Kantian constructivism in practical philosophy. The paper distinguishes between two readings of RF: on a weak reading, RF ranges over all (practical) reasoning but does not commit to constructivism, and on a strong version RF commits to constructivism but fails to meet its own test, and (...) so is self-defeating. The paper argues that RF, if understood strongly, depends for its reasonableness on reasons that cannot coherently be required to meet RF, so that RF cannot be the supreme principle of reason. The paper considers several responses to this problem in order to suggest that RF depends for its reasonableness on perfectionist considerations. (shrink)

In this paper I trace the development of one of the central debates of late twentieth-century moral philosophy—the debate between realism and what Rawls called “constructivism.” Realism, I argue, is a reactive position that arises in response to almost every attempt to give a substantive explanation of morality. It results from the realist’s belief that such explanations inevitably reduce moral phenomena to natural phenomena. I trace this belief, and the essence of realism, to a view about the nature of concepts—that (...) it is the function of all concepts to describe reality. Constructivism may be understood as the alternative view that a normative concept refers schematically to the solution to a practical problem. A constructivist account of a concept, unlike a traditional analysis, is an attemptto work out the solution to that problem. I explain how the philosophies of Kant and Rawls can be understood on this model. (shrink)

Two centuries after they were published, Kant's ethical writings are as much admired and imitated as they have ever been, yet serious and long-standing accusations of internal incoherence remain unresolved. Onora O'Neill traces the alleged incoherences to attempts to assimilate Kant's ethical writings to modern conceptions of rationality, action and rights. When the temptation to assimilate is resisted, a strikingly different and more cohesive account of reason and morality emerges. Kant offers a "constructivist" vindication of reason and a moral vision (...) in which obligations are prior to rights and in which justice and virtue are linked. O'Neill begins by reconsidering Kant's conceptions of philosophical method, reason, freedom, autonomy and action. She then moves on to the more familiar terrain of interpretation of the Categorical Imperative, while in the last section she emphasizes differences between Kant's ethics and recent "Kantian" ethics, including the work of John Rawls and other contemporary liberal political philosophers. (shrink)

This paper introduces a referential reading of Kant?s practical project, according to which maxims are made morally permissible by their correspondence to objects, though not the ontic objects of Kant?s theoretical project but deontic objects (what ought to be). It illustrates this model by showing how the content of the Formula of Universal Law might be determined by what our capacity of practical reason can stand in a referential relation to, rather than by facts about what kind of beings we (...) are (viz., uncaused causes). This solves the neglected puzzle of why there are passages in Kant?s works suggesting robust analogies between mathematics and ethics, since to universalize a maxim is to test a priori whether a practical object with that particular content can be constructed. An apparent problem with this hypothesis is that the medium of practical sensibility (feeling) does not play a role analogous to the medium of theoretical sensibility (intuition). In response I distinguish two separate Kantian accounts of mathematical apriority. The thesis that maxim universalization is a species of construction, and thus a priori, turns out to be consistent with the account of apriority that informs Kant?s understanding of actual mathematical practice. (shrink)