Keynesian expectations, epistemic authority and pluralism in economics: placebo and nocebo effects in normal and abnormal times

Prominent economists may provide expert guidance to assist the public in forming expectations. Using both Keynes' theory of conventional expectations formation and lay epistemology, this article argues that prominent economists may have sufficient 'epistemic authority' to encourage a self-fulfilling 'placebo/nocebo effect', meaning that widely and confidently-held expectations congruent with prominent economists' guidance encourage economic behaviours that promote the economic outcomes predicted by these economists. This article examines the peripherality of pluralism in the economics discipline as supporting these self-fulfilling dynamics insofar as it: (i) contributes to the public's capacity to identify and attribute epistemic authority to prominent economists, (ii) encourages sufficient convergence of prominent economists' expectational guidance that the public can adopt coherent and confident expectations based on this guidance and (iii) facilitates the public dissemination of this expectational guidance. The conclusion considers Keynesian 'abnormal times' (such as a Minskian expectational scenario) that may discredit the epistemic authority of prominent economists (and perhaps expert economic knowledge in general) and considers some implications of these circumstances for disciplinary pluralism.