Most people believe that extraterrestrial beings or porpoises or computers could someday be recognized as persons. Given the significant constitutional differences between these entities and ourselves, the general assumption appears to be that ‘person’ is not a natural kind term. David Wiggins offers an illuminating challenge to this popular dogma in ‘Locke, Butler and the Stream of Consciousness: and Men as a Natural Kind’. Wiggins does not claim that ‘person’ actually is a natural kind term; but he argues hard for the advantages of regarding it as something like a natural kind classification. The problem is that, whatever its merits, there are obvious and fatal objections to the view that person is a natural kind. My aim is to present a modification of the natural kind thesis which avoids these objections and retains the attractions of the basic position.