Pyrrhonism

Pyrrhonism, or Pyrrhonian skepticism, was a school of skepticism founded by Pyrrho in the fourth century BC. Believing that "knowledge of things is impossible and that we must assume an attitude of reserve", his school's existence was brief. It was revived by Aenesidemus in the first century BC and recorded by Sextus Empiricus in the late second century or early third century AD. A revival of the use of "Pyrrhonism" as a synonym for "skepticism" occurred during the seventeenth century.

Pyrrho of Elis (c. 360-c. 270 BCE) usually is credited with founding this school of philosophy. He traveled to India and studied with the "gymnosophists". From there, he brought back the idea that nothing can be known for certain. The senses are easily fooled, and reason follows too easily our desires. Pyrrhonism was a school of skepticism founded by his follower Aenesidemus in the first century BCE and recorded by Sextus Empiricus, who wrote the book series Against the Mathematicians (by some translated ‘Against the Professors’), in the late second century or early third century CE.

The New Academy Arcesilaus (c. 315-241 BCE) and Carneades (c. 213-129 BCE) developed more theoretical perspectives by which conceptions of absolute truth and falsity were refuted as uncertain. Carneades criticized the views of the Dogmatists, especially supporters of Stoicism, asserting that absolute certainty of knowledge is impossible. Sextus Empiricus (c. CE 200), the main authority we have for Greek skepticism, developed the position further, incorporating aspects of empiricism into the basis for asserting knowledge.

Whereas academic skepticism, with Carneades as its most famous adherent, claims that "nothing can be known, not even this", Pyrrhonian skeptics withhold any assent with regard to non-evident propositions and remain in a state of perpetual inquiry. They disputed the possibility of attaining truth by sensory apprehension, reason, or the two combined, and thence, inferred the need for total suspension of judgment (epoché) on non-evident matters. For any non-evident matter, a Pyrrhonist tries to make the arguments for and against such that the matter cannot be concluded, thus suspending belief. According to Pyrrhonism, even the statement that nothing can be known is dogmatic. They thus attempted to make their skepticism universal, and to escape the reproach of basing it upon a fresh dogmatism. Mental imperturbability (ataraxia) was the result to be attained by cultivating such a frame of mind.

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