Many have claimed that split-brain patients are actually two persons. I maintain that both the traditional separation argument and the more recent sophistication argument for the two persons interpretation are inadequate on conceptual grounds. An autonomy argument is inadequate on empirical grounds. Overall, theoretical and practical consequences weigh heavily in favor of adopting a one person interpretation.

Most contributors to the debate about brain death, including Dr. James Bernat, share certain assumptions. They believe that the concept of death is univocal, that death is a biological phenomenon, that it is necessarily irreversible, that it is paradigmatically something that happens to organisms, that we are human organisms, and therefore that our deaths will be deaths of organisms. These claims are supposed to have moral significance. It is, for example, only when a person dies that it is permissible to (...) extract her organs for transplantation.It is also commonly held that our univocal notion of death is the permanent cessation of integrated functioning in an organism and that the criterion for determining when this has occurred in animals with brains is the death of the brain as a whole – that is, brain death. The reason most commonly given for this is that the brain is the irreplaceable master control of the organism's integration. (shrink)

The majority of philosophers believe that the existence of spatially coincident entities is not only a coherent idea but that there are millions of such entities. What such philosophers do not countenance are spatially coincident entities of the same kind. We will call this ‘Locke's Thesis’ since the denial goes back to An Essay Concerning Human Understanding. It is there that Locke wrote, ‘For we never finding, nor conceiving it possible that two things of the same kind should exist in (...) the same place at the same time, we rightly conclude that, whatever exists anywhere at any time, excludes all of the same kind, and is there itself alone.’ It is not clear to me that the believer in spatially coincident entities can draw the ‘ontological line’ where Locke does. Many of the reasons that lead Locke and others to maintain that there exist spatially coincident entities of different kinds would also suggest that there are spatially coincident entities of the same kind. To illustrate this claim, a scenario of spatially coincident roads will be presented. (shrink)