Embryos, Four-Dimensionalism, and Moral Status

Philosophy journals have been full of discussions of Four-Dimensionalism in recent years. The rich resources of the Four-Dimensional metaphysics have been brought to bear upon many traditional philosophical problems. Alas, the implications of Four-Dimensionalism for bioethics have gone largely unexplored. Hud Hudson (1999, 2001) is the rare exception. Relying upon a Four-Dimensional metaphysics, he argues that there is little reason to identify the human embryonic animal and human person. He makes the intriguing claim that if abortion is wrong, then it isn’t 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” (2001, p. 153). Hudson admits that if he were convinced of the truth of Three-Dimensionalism, then he would find it more compelling to identify human persons and human animals than accept that they are distinct entities though composed of the same atoms (2001, p. 130). Such an identification would lead him to claim that the human person is an animal with biological persistence conditions, coming into existence with the onset of life and going out of existence when life is extinguished. So if Hudson were an advocate of Three-Dimensionalism, then he might very well agree with such staunch defenders of human embryonic life as Tollefsen and George who argue that mindless embryos shouldn’t be aborted because they are persons (George and Tollefsen, 2008). But if Hudson’s favored Four-Dimensionalist metaphysics is true, as well as his claim that the approach removes the reasons to identify the person and animal, then perhaps it is George and Tollefsen who should drop their opposition to abortion for they acknowledge that the exalted moral status of embryos depends upon their identity with persons.