Ordinary Moral Knowledge and Philosophical Ethics in Sidgwick and Kant

Abstract

Sidgwick considered Kant as one of his masters. However, he never devoted any systematic attention to Kant’s ethical theory; moreover, in The Methods of Ethics he concluded that Kantian ethics is inadequate to guide moral life. I review Sidgwick’s references to Kant in order to show that – along with basic differences − there are significant similarities in the main project of the two philosophers; and I suggest that, should Sidgwick have deepened his understanding of Kant, he might have realised that Kantian ethics offered a somewhat different way to accomplish the philosophical project he was interested in, that is, the systematisation of the morality of common sense through the establishment of certain moral axioms. I also suggest that Sidgwick’s misunderstanding of the “formula of humanity” is at the heart of his final dismissal of Kant’s ethics and that deepening his understanding of Kant might have led Sidgwick to revise his views on the rationality of egoism, thereby opening the possibility to solve the dualism of practical reason. Finally, I offer some speculations on the reasons why Sidgwick never attempted a thorough confrontation with Kant, suggesting that both his distaste for Kant’s metaphysics and his Millian utilitarian bias deterred him from it.