Epistemic Vigilance DAN SPERBER, FABRICE CL ´ EMENT, CHRISTOPHE HEINTZ, OLIVIER MASCARO, HUGO MERCIER, GLORIA ORIGGI AND DEIRDRE WILSON Abstract: Humans massively depend on communication with others, but this leaves them open to the risk of being accidentally or intentionally misinformed. To ensure that, despite this risk, communication remains advantageous, humans have, we claim, a suite of cognitive mechanisms for epistemic vigilance. Here we outline this claim and consider some of the ways in which epistemic vigilance works in mental and social life by surveying issues, research and theories in different domains of philosophy, linguistics, cognitive psychology and the social sciences. 1. Intro duct ion We claim that humans have a suite of cognitive mechani sms for epistemic vigilanc e, targeted at the risk of being misinformed by others. Here we present this claim and consider some of the ways in which epistemic vigilance works in mental and social life. Our aim is to integrate into a coherent topic for further research a wide range of assumptions developed elsewhere by ourselves or others, rather than to present detailed arguments for each. Humans are exceptional among animals for both the richness and strength of their cognitive abilities and the extent to which they rely on a wide variety of information communicated by others. These two traits are linked. On the one hand, it would not be possible to rely so heavily on rich communication in the absence of specie s-specifi c cognitive abilitie s, in partic ular language and advanced mindre ading. On the other hand, these individual abilities would not develop or functio n properly in the absence of cognitive skills, conceptual tools, and background knowledge acquired from others. How reliable are others as sources of information? In general, they are mistaken no more often than we are—after all, ‘we’ and ‘they’ refer to the same people—and they know things that we don’t know. So it should be advantageous to rely even blindly on the competence of others. Would it be more advantageous to modulate We are grateful to two anonymous referees for useful suggestions and comments on an earlier version of this article and to the Centre for the Study of Mind in Nature at the University of Oslo for supporting our work. Addre ss for corr espon dence : Dan Spe rbe r, Ins tit ut Jea n-Nico d —Pav illo n Jar din , Eco le Normale Sup ´ erieure, 29, rue d’Ulm 75005 Paris, France. Email: [email protected] Mind & Language, Vol. 25, No. 4 Septemb er 2010, pp. 359– 393. © 2010 Blackwell Publishing Ltd