The Ghosts of the Agora: Classical Rhetoric as a Framework for Understanding Misinformation, Populism, and Polarization in Health Communication

What constitutes quality health information is conventionally framed in epistemic terms: accuracy, evidential rigor, methodological transparency. This article argues that such criteria, while necessary, are insufficient. Health communication operates under conditions of uncertainty, competing authority, and emotional intensity that render it fundamentally rhetorical. Drawing on primary texts from the Sophistic tradition, Plato, Aristotle, Cicero, and Quintilian, and integrating modern rhetorical theories from Burke, Toulmin, and Bormann, this article constructs a four-dimensional framework, namely, epistemic grounding, structural integrity, civic responsibility, and interpretive equity, for diagnosing how health misinformation, populism, and ideological polarization degrade public discourse. Contributing to the agenda of the Nature Medicine Commission on Quality Health Information for All, the article demonstrates that classical rhetoric provides precise diagnostic instruments for the pathologies of modern health information, pathologies that are structurally ancient even when technologically amplified.