Salient social identities have long appeared to shape what we believe and know. But do social identities also shape how we know? This essay argues that performances of “lay epistemology” by populist leaders may shape group norms in ways that encourage supporters to orient to their worlds more through intuition and emotion and less through evidence and data (or at least to report that they do, thus constituting a form of “expressive epistemology”). We summarize research on the positive link between populist attitudes, valuing intuition and emotion over evidence and data, and belief in misinformation and conspiracy theories, and then explore how these relationships may be mutually reinforcing – and strategically beneficial to populist leaders.