  Sextus Empiricus was a Pyrrhonian Skeptic living probably in the second or third century CE, many of whose works survive, including the Outlines of Pyrrhonism, the best and fullest account we have of Pyrrhonian skepticism (a kind of skepticism named for Pyrrho (see entry on Ancient Skepticism)).   Pyrrhonian skepticism involves having no beliefs about philosophical, scientific, or theoretical matters—and according to some interpreters, no beliefs at all, period. Whereas modern skepticism questions the possibility of knowledge, Pyrrhonian skepticism questions the rationality of belief: the Pyrrhonian skeptic has the skill of finding for every argument an equal and opposing argument, a skill whose employment will bring about suspension of judgment on any issue which is considered by the skeptic, and ultimately, tranquillity.