Abstract

The paper is concerned with how neo-Lockean accounts of personal identity should respond to the challenge of animalist accounts. Neo-Lockean accounts that hold that persons can change bodies via brain transplants or cerebrum transplants are committed to the prima facie counterintuitive denial that a person is an (biologically individuated) animal. This counterintuitiveness can be defused by holding that a person is biological animal (on neo-Lockean views) if the “is” is the “is” of constitution rather than the “is” of identity, and that a person is identical with an animal in a sense of “animal” different from that which requires the persistence conditions of animals to be biological. Another challenge is the “too many minds problem”: if persons and their coincident biological animals share the same physical properties, and mental properties supervene on physical properties, the biological animal will share the mental properties of the person, and so should itself be a person. The response to this invokes a distinction between “thin” properties, which are shared by coincident entities, and “thick” properties which are not so shared. Mental properties, and their physical realizers, are thick, not thin, so are not properties persons share with their bodies or biological animals. The paper rebuts the objection that neo-Lockean accounts cannot explain how persons can have physical properties. To meet a further problem it is argued that the biological properties of persons and those of biological animals are different because of differences in their causal profiles