 These challenges are inherited by two accounts that seek to base moral status on the possession of a “modal property.” Shelley Kagan (2016) and Jonathan Surovell (forthcoming) argue that beings who had, or could have had, the psychological capacities of typical human beings are their moral equals. According to both accounts, human beings who lost, or never had, those capacities due to illness or impairment still have the modal property that they could have had them, and this property confers full moral status. That property is not possessed by members of most other species, who could only have acquired those capacities in quite distant possible worlds. As Surovell puts it, “[d]isability but not species membership is a matter of luck” (21).