Academic Skeptic School of Ancient Greek Philosophy Texts

Academic Skepticism arose in the Platonic Academy at Athens around 266 BCE, when Arcesilaus became head of the school and turned it from dogmatic Platonism towards skeptical inquiry, presenting this turn as a revival of a skeptical thread in Plato's later dialogues.

The school's central position was ἀκαταληψία, the view that firm knowledge (κατάληψις) of things as they are is impossible. The Academics argued that no infallible criterion of truth exists, and pressed this claim directly against the Stoic doctrine of the καταληπτική φαντασία, the cognitive impression that the Stoics held to be the foundation of knowledge.

Because sensations are relative and reason can marshal arguments of equal strength on opposite sides of any question, the Academics held that universal ἐποχή, the suspension of judgement, was the only rational response. They practised this suspension in order to reach ἀταραξία, a state of imperturbability. Unlike the Pyrrhonian sceptics, who suspended judgement even on the question whether knowledge is possible, the Academics asserted flatly that it is not. For the conduct of life they fell back on the πιθανόν, the plausible; Carneades worked this into a hierarchy of plausibility, in which an impression could be plausible in itself, remain uncontradicted by other impressions, and survive thorough testing.

The Academic method was dialectical. Its practitioners argued against the positive doctrines of other schools and exposed their inconsistencies, without asserting dogmas of their own.

The skeptical phase of the Academy ran from Arcesilaus, its sixth scholarch (c. 318–243 BCE), to Carneades (c. 214–129 BCE), who refined the doctrine of the plausible and led a famous philosophical embassy to Rome in 155 BCE, and on to Philo of Larissa (c. 159–84 BCE), the last undisputed skeptical scholarch, who softened the position in a fallibilist direction. Cicero (106–43 BCE), whose <cite>Academica</cite> is the principal source for the school, studied in this tradition. Around 90 BCE Antiochus of Ascalon rejected skepticism and revived a dogmatic Platonism, an event usually taken to close the skeptical Academy, though individual skeptics such as Favorinus carried the tradition forward. Because the school worked through oral debate, its arguments survive mainly in the reports of Cicero and of later writers such as Sextus Empiricus.