 We have now seen some of the problems that face those who develop knowledge within a community. In recent years philosophers have turned to formal methods to understand some of these social aspects of belief and knowledge formation. There are broadly two approaches in this vein. The first comes from the field of formal epistemology, which mostly uses proof-based methods to consider questions that mostly originate within individual-focused epistemology. Some work in this field, though, considers questions related to, for example, judgment aggregation and testimony. The second approach, sometimes dubbed “formal social epistemology”, stems largely from philosophy of science, where researchers have employed modeling methods to understand the workings of epistemic communities. While much of this work has been motivated by a desire to understand the workings of science, it is often widely applicable to social aspects of belief formation.