In The Modularity of Mind 1 Jerry Fodor argues that higher cognition has certain holistic characteristics in virtue of which it can be regarded as, to use Fodor's terms, informationally unencapsulated and nonmodular. This leads Fodor to offer a depressing prognosis for the science of higher cognition. Higher cognition might be tractable if it were divisible into the operations of relatively restricted and independently investigable subsystems; but its essentially global character precludes this division, and thereby makes it a most unpromising field for scientific investigation. These are large claims, and one could hardly hope to settle them in short compass. I guess it is clear that this wasn't Fodor's intent, and it is certainly not mine. In Sections I and II, I approach Fodor's argument with a view to uncovering one of its guiding intuitions. For I think that, in large measure, the argument rests upon an idealized conception of rationality. And because of this I do not see how the argument could genuinely yield Fodor's conclusion. Even so, Fodor does open up the prospect that higher cognition might follow the principles suggested by this idealization of rationality, and in that event Fodor's depressing prognosis would be difficult to avoid. In the face of this, I believe it is reasonable to view Fodor's remarks as providing cognitive theorists with a fairly persuasive reason for not allowing that rationality is built into cognitive process in anything like the way that Fodor supposes. The science of higher cognition had best proceed on the assumption that some other design principles better accord with the facts of human rationality. This assumption is not without some degree of empirical support. Sections III and 1V are given over to analyses of some empirical psychological studies which conjointly suggest that modularity in higher cognition is not only compatible with human rationality but that it actually underlies it. As I say, I don't wish to conclude that Fodor's holistic hypothesis must be wrong. Yet since