 According to Frederik Kaufman (2016, p. 63), this thought experiment (perhaps tweaked a bit) might provide a way in which a human organism could have come into existence far earlier than she did, but it does not provide a way in which a person could have come into existence far earlier. “Persons (properly understood) cannot exist earlier than they do.” He bases this view on the assumption—challenged by animalists but defended by Parfit—that persons are objects (distinct from organisms) with psychological persistence conditions, chief among which is psychological continuity, together with the assumption that “if mental continuity is constitutive of personal identity, then when a particular consciousness emerges is essential to that person.”