Building on the results of the Groundwork and the Critique of Practical Reason, Kant finally published his system of moral philosophy in two volumes in 1797. By then, he had been planning to write a Metaphysics of Morals for three decades; but only the title remained unchanged while the basic principles of his theoretical and practical philosophy changed dramatically. While for many years academic moral philosophy focused mainly on Kant's earlier ethical treatises, there has recently been much interest in this later and perhaps more mature work on moral...