How To Be a Happy Skeptic

Come join the Philly Stoa as we continue our series on How to Be a (Happy) Skeptic, turning from Massimo Pigliucci's introductory essay to Chapter One of the book itself: "The Fundamental Question: How Do We Know?"

Cicero warned that we should not be too confident in our belief of anything. The question of how we know anything turns out not to be an abstraction reserved for seminar rooms. It is what we are doing, mostly without noticing, every time we look at something and decide what it is.

What the ancient skeptics offer is not paralysis. Cicero's term probabilis names something closer to a graded scale of confidence: a claim can be plausible, or persuasive, or consistent with everything else we know, or as well-examined as anything we call scientific, and still never quite certain. It is an ancient version of something we would now describe in Bayesian terms, and it points…