Bibliogr. s. 50-51

One of the central issues of contemporary philosophy concerns the definition of the person. Many philosophers and bioethicists have sought to determine the basis for ascribing personhood, and to resolve the associated question of whether only human beings may be properly granted this status. Two contemporary thinkers have played a leading role in this debate, namely Robert Spaemann and Peter Singer. The former, coming from the tradition of Christian thought, seeks to demonstrate that the personality of a human being begins when he or she is conceived and ends with his or her death. In his opinion, only God, as the source of all life, has a right to exercise authority over human destiny. The opposite position is defended by the Australian philosopher Peter Singer. His philosophical views have emerged from the tradition of empiricist thought initiated by Democritus and expanded on later, above all, by John Locke. Singer postulates a descriptive theoretical account of persons, claiming that personhood results from the possession of a set of qualitative features, namely: to become a person, a human being ought to have certain properties, such as self-awareness, rationality of thought, or the possession of preferences - without these, he would say, one cannot even talk about persons. This paper seeks to confront the tenets of personalist ethics (as in Spaemann) with those of preference-based utilitarianism (Peter Singer), presenting the metaphysical, ontological and cognitive commitments that make up these two positions, but also asking whether there is any shared set of underlying concerns that could furnish a basis for dialogue between them.