This chapter considers how sharp the temporal boundaries of a subject's existence are, when viewed from the perspective of the C-theory. Can we fade into or out of existence, or are the boundaries of our lives utterly sharp? One difficulty is arriving at a general idea of the conditions under which potentialities can persist through menacing circumstances. Some relevant distinctions are drawn. A second and rather more difficult question is whether or not the kind of potential for experience our brains possess is all-or-nothing. An extension of Unger's spectrum of congenial decomposition suggests that the experiential potential of our brains can depend on the presence or absence of a single neuron. However, this result is also open to challenge. The conclusion: while we can in fact reasonably take our experiential capacities to be all-or-nothing, so doing is not without its difficulties.
Keywords: experiential capacities, brains, all-or-nothing, spectrum of congenial decomposition