 Machuca, who pursued his undergraduate and graduate studies in Argentina, obtaining his Ph.D. at UBA, is currently a researcher at CONICET and the editor (with Duncan Pritchard) of the International Journal for the Study of Skepticism (2011). Having initially devoted himself to examining Sextus’s Pyrrhonism and moral skepticism, he has more recently focused also on a systematic discussion of skepticism in relation to epistemological issues. He has looked at the relevance of Pyrrhonism to contemporary theories of knowledge and justification and, in particular, to the present-day debate over the epistemic significance of disagreement, defending a neo-Pyrrhonian stance (Machuca 2013b, 2015a, 2017a, 2022). He has also examined the connection between disagreement and skepticism in general, arguing inter alia that a radical disagreement-based skepticism cannot be dismissed out of hand as being patently untenable or absurd (Machuca 2015b, 2017b).