What is skepticism? And how should a good skeptic approach her commitment to the field? These are crucial questions that most of us take for granted but that—I think—are worth pause to ponder and reevaluate from time to time. Which is what I intend to do in this article, introducing readers to an approach called “virtue epistemology,” which has much to say of relevance to the conscientious skeptic.
The ethos of the modern skeptical movement, the one that traces its origins to Paul Kurtz and others in the 1970s, is perhaps best encapsulated by the phrase “extraordinary claims require extraordinary evidence,” popularized by Carl Sagan but first articulated by Marcello Truzzi as “an extraordinary claim requires an extraordinary proof.” Both versions, in turn, owe much to two illustrious antecedents: Pierre-Simon Laplace, who in 1812 wrote: “The weight of evidence for an extraordinary claim must be proportioned to its strangeness,” and David Hume, who said in 1748: “A wise man . . . proportions his belief to the evidence.”
Skepticism has evolved over the past several decades, expanding the circle of its concerns and therefore the type of claims it considers “extraordinary” and thus in need of proportional evidence in order to be verified. Moreover, skepticism has developed nationally and internationally as a powerful grassroots movement for the advocacy of science and critical thinking more generally. Broadly speaking, we can distinguish between those areas of inquiry that fall under “classic” skepticism—which include astrology, UFOlogy, psychics, paranormal experiences, ghosts, Bigfoot, and the like—and those additional issues that have contributed to evolve contemporary skepticism: intelligent design creationism, vaccine denialism, climate change denialism, and so forth. Some skeptics have even ventured into criticism of areas of academic research and scholarship, such as the replicability issue in psychology and the social sciences, the debate about the value of string theory in physics, and the general usefulness of philosophy.