The beliefs of a single agent are typically treated in logic and philosophy as a single modality or epistemic attitude. I argue that it is better to treat belief as a loosely related family of related modalities. This approach to belief, along with mechanisms for constructing modalities and for activating a modality that is appropriate for a specifc reasoning situation, seems to provide a much better model of the relation of belief to intention in deliberative reasoning. I discuss this and other applications of this more flexible conception of belief and similar attitudes.