Abstract
This paper argues that the problem of expertise calls for a rapprochement between social epistemology and argumentation theory. Social epistemology has tended to emphasise the role of expert testimony, neglecting the argumentative function of appeals to expert opinion by non-experts. The first half of the paper discusses parallels and contrasts between the two cases of direct expert testimony and appeals to expert opinion by our epistemic peers, respectively. Importantly, appeals to expert opinion need to be advertised as such, if they are to sway an epistemic peer. The second half of the paper sketches a theoretical framework for thinking about assessments of expertise in a unified way, via a ‘default and challenge’ model that emphasises the need for a version of conversational scorekeeping. It is through such scorekeeping that interlocutors can track and coordinate their differences in epistemic outlook. The paper concludes with a genealogical perspective on the function of (attributions of) expertise: acceptance of another’s appeal to expert opinion may be construed as tacit agreement that inquiry, for now, has been taken far enough