Abstract

Searching for a rational method of moral reasoning, Henry Sidgwick concludes that practical reason is inconsistent and sometimes directs us to actions that are contradictory. Our ultimate duty is in fact to achieve both our own, particular happiness and the happiness at all. We have duties both of a selfish and of a utilitarian nature. In a situation of conflict, when for the public good we must sacrifice our own interests, reason is not able to indicate to us what course of action should be followed. Finally, we must admit that we cannot entirely rationalize our moral choices. The so-called problem of the dualism of practical reason has been and is discussed by many eminent philosophers, including Roger Crisp, John Skorupskiego and Derek Parfit. This paper is an attempt to highlight the considerations of Sidgwick's dualism of practical reason, the sources of dualism and the contemporary reception of this extremely serious problem for ethics.