No aspect of Locke's Essay has received more attention than his theory of personal identity. Yet surprisingly little attention has been given to the intellectual context in which it was written. This is particularly noteworthy in that the chapter in which the theory is developed, “Of Identity and Diversity” (II,xxvii), has a history quite independent of the bulk of the Essay. Added only in the second edition (1694), the theory constitutes a rather late chapter in Locke's intellectual biography. In contrast to other major themes of the Essay, such as the origin of our ideas, substance, power, essence, etc., which received their early development in the various drafts of the Essay (the first being dated 1670), Locke's views on personal identity were apparently first formulated in a note in his 1683 journal.