 Last but not least, abduction plays a central role in some important philosophical debates. See Shalkowski 2010 on the place of abduction in metaphysics (also Bigelow 2010), Krzyżanowska, Wenmackers, and Douven 2014 and Douven 2016a for a possible role of abduction in the semantics of conditionals, and Williamson 2017 for an application of abduction in the philosophy of logic. Arguably, however, abduction plays its most notable philosophical role in epistemology and in the philosophy of science, where it is frequently invoked in objections to so-called underdetermination arguments. Underdetermination arguments generally start from the premise that a number of given hypotheses are empirically equivalent, which their authors take to mean that the evidence—indeed, any evidence we might ever come to possess—is unable to favor one of them over the others. From this, we are supposed to conclude that one can never be warranted in believing any particular one of the hypotheses. (This is rough, but it will do for present purposes; see Douven 2008 and Stanford 2009, for more detailed accounts of underdetermination arguments.) A famous instance of this type of argument is the Cartesian argument for global skepticism, according to which the hypothesis that reality is more or less the way we customarily deem it to be is empirically equivalent to a variety of so-called skeptical hypotheses (such as that we are beguiled by an evil demon, or that we are brains in a vat, connected to a supercomputer; see, e.g., Folina 2016). Similar arguments have been given in support of scientific antirealism, according to which it will never be warranted for us to choose between empirically equivalent rivals concerning what underlies the observable part of reality (van Fraassen 1980).