John Locke's theory of personal identity underlies all modern discussion of the nature of persons and selves--yet it is widely thought to be wrong. In this book, Galen Strawson argues that in fact it is Locke's critics who are wrong, and that the famous objections to his theory are invalid. Indeed, far from refuting Locke, they illustrate his fundamental point. Strawson argues that the root error is to take Locke's use of the word "person" as merely a term for a standard persisting thing, like "human being." In actuality, Locke uses "person" primarily as a forensic or legal term geared specifically to questions about praise and blame, punishment and reward. This point is familiar to some philosophers, but its full consequences have not been worked out, partly because of a further error about what Locke means by the word "conscious." When Locke claims that your personal identity is a matter of the actions that you are conscious of, he means the actions that you experience as your own in some fundamental and immediate manner. Clearly and vigorously argued, this is an important contribution both to the history of philosophy and to the contemporary philosophy of personal identity.