An examination and defence of the concept of personality, long central to Western moral culture but now increasingly under attack, by a leading European philosopher. It takes issue with major contemporary philosophers, especially in the English-speaking world (such as Parfit and Singer), who have contributed to the eclipse of the idea, and traces the debate back to the foundations of modern philosophy in Descartes and Locke. There are extended discussions of the sources of the idea in Christian theology and its development in Western philosophy. There are also a number of pointed discussions of pressing practical questions - for example, our treatment of the severely disabled human and the moral status of intelligent non-human animals. The book covers a great deal of ground before coming to a focused conclusion: all human beings are persons - and perhaps all porpoises, too!