 But arguably, Kant’s view of personhood does not distinguish all and only humans as morally considerable. Personhood is not, in fact, coextensive with humanity when understood as a general description of the group to which human beings belong. And the serious part of this problem is not that there may be some extra-terrestrials or deities who have rational capacities. The serious problem is that many humans are not persons. Some humans—i.e., infants, children, people in comas—do not have the rational, self-reflective capacities associated with personhood. This problem, unfortunately known in the literature as the problem of “marginal cases”, poses serious difficulties for “personhood” as the criterion of moral considerability. Many beings whose positive moral value we have deeply held intuitions about, and who we treat as morally considerable, will be excluded from consideration by this account.