This paper considers the question whether a psychological approach to personal identity can be formulated within an endurantist, as opposed to four-dimensionalist, framework. Trenton Merricks has argued that this cannot be done. I argue to the contrary: a perfectly coherent endurantist version of the psychological approach can indeed be formulated.

The rich resources of the Four-Dimensional metaphysics have been brought to bear upon many traditional philosophical problems in recent years. Alas, the implications of Four-Dimensionalism for bioethics have gone largely unexplored. Hud Hudson is the rare exception. Relying upon a Four- Dimensional metaphysics of temporal parts and a belief in unrestricted composition, he argues that there is little reason to identify the perduring human embryonic animal and the perduring human person. He makes the intriguing claim that if abortion is wrong, (...) then it is not because the human animal within its mother’s womb is a person. This he rightly claims “is a very significant result” for “an overwhelming amount of the literature on abortion and infanticide (as well as much of the public debate on these topics) seems to turn on the question of whether or not the human fetus is a person.” [3, p. 153]. (shrink)