 One strategy for defending the higher-brain approach is to appeal to the essence of human persons on the understanding that this essence requires the capacity for consciousness (see, e.g., Bartlett and Youngner 1988; Veatch 1993; Engelhardt 1996, 248; Rich 1997; and Baker 2000, 5). “Essence” here is intended in a strict ontological sense: that property or set of properties of an individual the loss of which would necessarily terminate the individual's existence. From this perspective, we human persons—more precisely, we individuals who are at any time human persons—are essentially beings with the capacity for consciousness such that we cannot exist at any time without having this capacity at that time. We go out of existence, it is assumed, when we die, so death involves the loss of what is essential to our existence.