We commonly ascribe beliefs and similar attitudes to groups. For instance, we say that a foreign government believes that members of the press are spies, or that a corporation denies that its product is harmful to the environment. Sometimes, it seems that in such cases, we are simply ascribing to the group the shared beliefs of its members. But there are other cases in which it appears we are referencing an independent subject of the belief or attitude – the government or the corporation, over and above its members. Puzzles abound.

In The Epistemology of Groups (Oxford 2021), Jennifer Lackey develops a unified account of group belief, justified group belief, group knowledge, and group assertion. Intriguingly, this account serves ultimately to allow us to make sense of group lies.