Abstract
<jats:title>Abstract</jats:title> <jats:p>The Social Roots of Delusions argues that human sociality—our nature as highly social animals—is crucial for understanding what delusions are and how they are formed. We are a deeply cooperative and cultural species, reliant on others not only for our survival and success but for our ability to make sense of the world. Moreover, this world is itself deeply social, featuring complex systems of norms, reputations, gossip, surveillance, and partner choice, as well as high-stakes competition for prestige and power among individuals and shifting coalitions. This account of human sociality provides the background for Williams et al.'s analysis of delusions. First, the authors argue that what it means to be delusional is best understood in the context of norm-governed, social-epistemic practices of flagging and gatekeeping. Treating beliefs as delusional is part of an ancient social practice in which members of epistemic communities express bafflement at certain beliefs and signal that those who endorse them are “rational lost causes,” unreachable by ordinary processes of communication, persuasion, and rational argument. Second, the authors argue that human sociality is also crucial for understanding how delusions—including both clinical delusions and popular delusions—are formed and maintained. Popular delusions emerge from interactions between socially motivated cognition and complex forms of social scaffolding, whereas clinical delusions arise when social isolation and mistrust cause individuals to lose access to the corrective testimony on which people rely to regulate their beliefs.</jats:p>