This chapter explains how John Locke's work on epistemology, politics, and economy can be read as a sustained meditation on the relationship of risk and trust. The extensive literature on trust and authority in Locke's work establishes that he thinks citizens' trust in the state helps them organize and survive in the face of uncertainty, as well as manage the risks they might find in the future. This chapter argues that Lockean political trust is actually more closely related to risk than it appears at first glance. Political trust, Locke theorizes, is actually underwritten by the perpetual work of risk calculation and probabilistic reasoning by citizens. His work shows that if a strong central state is the institution that manages political and economic risk for subjects, then those subjects still must scrutinize the state as a new risk, using whatever cognitive tools they have at their disposal.