 A second reason offered for discussing nonconceptualism at the level of state type rather than at the level of content is that it allows for a meaningful debate about nonconceptualism even if one holds that all content is nonconceptual. Stalnaker (1984, 1998), for example, argues that all content should be understood in terms of sets of possible worlds. If that is the case, then the difference between the propositional attitudes and perception should be elucidated in terms extrinsic to the type of content involved in these states. This can be achieved if we think that the propositional attitudes, but not perceptual states, are concept-dependent; that is, if we think that having propositional attitudes but not perceptual states requires the subject of those attitudes to possess certain concepts. This reasoning holds equally well if one thinks that all content is conceptual. In such a case, one is forced to explain the difference between different types of content involving states in terms extrinsic to the nature of their contents; the state-view is one way of explaining this distinction, by appeal to the capacities required of a subject if she is to undergo such states.