Greece & Rome · fl. 2nd–3rd c. CE
Sextus Empiricus
Physician whose books are our main source for ancient skepticism
Collected the “modes” that lead to suspension of judgement, such as conflicting appearances and the problem that every proof needs a further proof. He presented skepticism not as a doctrine but as an ability and a way of life.
Life and thought
Almost nothing is known of Sextus Empiricus’ life, not even his city or exact century: he lived some time between about 100 and the early 3rd century CE. His surname shows he was a doctor of the Empiric school, which relied on observation rather than theories about hidden causes. His surviving books, the Outlines of Pyrrhonism and the longer Against the Mathematicians (that is, the learned), are our fullest source for ancient scepticism, and much of what we know of Stoic and other Hellenistic theories comes from his attacks on them.
Sextus presents scepticism not as a doctrine but as an ability: to set appearances and arguments against each other so evenly that judgement is suspended, after which tranquillity follows “as a shadow follows a body”. His toolkit includes the Ten Modes (things appear differently to different animals, people, senses and circumstances) and the Five Modes of Agrippa, among them the regress: every proof needs a further proof. Printed in Latin in the 1560s, his books set off the early modern sceptical crisis that Montaigne explored and Descartes tried to answer.
Works
Shaped by
c. 360–270 BCEPyrrhoFounder of Pyrrhonian skepticism, who went to India with AlexanderShaped
1533–1592Michel de MontaigneMontaigne had skeptical maxims, several from Sextus, painted on the beams of his library.Argued against
c. 279–206 BCEChrysippusSextus spends long books dismantling Stoic logic and its criterion of truth.Meanwhile, in other traditions
c. 2nd c. BCE – 2nd c. CE (traditional author)Akṣapāda GautamaTraditional author of the Nyāya Sūtrac. 150–250NāgārjunaFounder of Madhyamaka, revered as a ‘second Buddha’On the record
Sextus Empiricus flourished c. 200 CE.
Nothing in his works fixes his dates. Estimates run from about 100 CE to the first half of the 3rd century, and he may already have been known by the end of the 2nd; “c. 200” is a convenient middle, not evidence. His name marks him as a doctor of the Empiric school of medicine.
Sources: Stanford Encyclopedia of Philosophy, “Sextus Empiricus”