Sextus Empiricus (c. 160-210 AD), was a physician and philosopher, and has been variously reported to have lived in Alexandria, Rome, or Athens. His philosophical work is the most complete surviving account of ancient Greek and Roman skepticism.
In his medical work, tradition maintains that he belonged to the "empiric" school (see Asclepiades), as reflected by his name. However, at least twice in his writings, Sextus seems to place himself closer to the "methodic" school, as his philosophical views imply.
Sextus Empiricus's three known works are the Outlines of Pyrrhonism
(Πυῤῥώνειοι ὑποτύπωσεις or Pyrrhōneioi hypotypōseis
), and two distinct works preserved under the same title, Against the Mathematicians
), one of which is probably incomplete.
The first six books of Against the Mathematicians are commonly known as Against the Professors, but each book also has a traditional title (Against the Grammarians (book I), Against the Rhetoricians (book II), Against the Geometricians (book III), Against the Arithmeticians (book IV), Against the Astrologers (book V), Against the Musicians (book VI)). It is widely believed that this is Sextus's latest and most mature work.
Books VII-XI of Against the Mathematicians form an incomplete whole; scholars believe that at least one, but possibly as many as five books, are missing from the beginning of the work. The extant books have the traditional titles Against the Logicians (books VII-VIII), Against the Physicists (books IX-X,) and Against the Ethicists (book XI). Against the Mathematicians VII-XI is sometimes distinguished from Against the Mathematicians I-VI by giving it the title Against the Dogmatists (in which case Against the Logicians are called books I-II, Against the Physicists are called books III-IV, and Against the Ethicists is called book V, despite the fact that it is commonly believed that the beginning of the work is missing and it is not known how many books might have preceded the extant books).
Note that none of these titles except Adversus Mathematicos (Against the Mathematicians) and Πυῤῥώνειοι ὑποτύπωσεις (Outlines of Pyrrhonism), are found in the manuscripts.
Sextus Empiricus raised concerns which applied to all types of knowledge. He doubted the validity of induction
long before its most well known critic David Hume
, and raised the regress argument
against all forms of reasoning:
Because of these and other barriers to acquiring true beliefs, Sextus Empiricus advises that we should suspend judgment about virtually all beliefs, that is, we should neither affirm any belief as true nor deny any belief as false. This view is known as Pyrrhonian skepticism, as distinguished from Academic skepticism, as practised by Carneades, which, according to Sextus, denies knowledge altogether. Sextus did not deny the possibility of knowledge. He criticizes the Academic skeptic's claim that nothing is knowable as being an affirmative belief. Instead, Sextus advocates simply giving up belief: that is, suspending judgment about whether or not anything is knowable. Only by suspending judgment can we attain a state of ataraxia (roughly, 'peace of mind'). Sextus did not think such a general suspension of judgment to be impractical, since we may live without any beliefs, acting by habit.
Sextus allowed that we might affirm claims about our experience (e.g., reports about our feelings or sensations). That is, for some claim X that I feel or perceive, it could be true to say "it seems to me now that X." However, he pointed out that this does not imply any objective knowledge of external reality. For while I might know that the honey I eat tastes sweet to me, this is merely a subjective judgment, and as such may not tell me anything true about the honey itself.
Sextus severely criticised the Stoics throughout his work, especially the Stoic view that signs can indirectly reveal something about the non-evident.
Interpretations of Sextus's philosophy along the above lines have been advocated by scholars such as Myles Burnyeat, Jonathan Barnes, and Benson Mates.
Michael Frede, however, defends a different interpretation, according to which Sextus does allow beliefs, so long as they are not derived by reason, philosophy or speculation; a skeptic may, for example, accept common opinions in the skeptic's society. However, the content of such beliefs is purely conventional or subjective. Thus, on this interpretation, the skeptic may well entertain the belief that God does or does not exist or that virtue is good. But he may not believe that such claims are true by nature.
The Ten Modes of Pyrrhonism
Pyrrhonism is more a mental attitude or therapy as opposed to a theory. It involves setting things in opposition and owing to the equipollence of the objects and reasons, one suspends judgement. "We oppose either appearances to appearances or objects of thought to objects of thought or alternando.
The ten modes induce suspension of judgement and in turn a state of mental suspense followed by ataraxia
. If ever one is in a position in which they are unable to refute a theory, Pyrrhonists reply "Just as, before the birth of the founder of the School to which you belong, the theory it holds was not as yet apparent as a sound theory, although it was really in existence, so likewise it is possible that the opposite theory to that which you now propound is already really existent, though not yet apparent to us, so that we ought not as yet to yield assent to this theory which at the moment seems to be valid. These ten modes
were originally listed by Aenesidemus
- "The same impressions are not produced by the same objects owing to the differences in animals."
- The same impressions are not produced by the same objects owing to the differences among human beings.
- The same impressions are not produced by the same objects owing to the differences among the senses.
- Owing to the "circumstances, conditions or dispositions." For example drunk as opposed to sober, sick as opposed to well, etc.
- "Based on positions, distances, and locations; for owing to each of these the same objects appear different;" The same tower appears rectangular at close distance and round from far away.
- “we deduce that since no object strikes us entirely by itself, but along with something else, it may perhaps be possible to say what the mixture compounded out of the external object and the thing perceived with it is like, but we would not be able to say what the external object is like by itself…
- "...based, as we said, on the quantity and constitution of the underlying objects, meaning generally by "constitution" the manner of composition." Goat horn appears black when intact and appears white when ground up.
- “…since all things appear relative, we will suspend judgement about what things exist absolutely and really existent. "Do things which exist "differentially" or "have a distinct existence of their own" differ from relative things or not? If they do not differ, then they too are relative; but if they differ, then, since everything which differs is relative to something..., things which exist differentially are relative.
- "Based on constancy or rarity of occurrence." The sun is more amazing than a comet, but because we see the sun daily and the comet rarely, the latter commands our attention.
- "...mainly concerned with Ethics, being based on rules of conduct, habits, laws, legendary beliefs, and dogmatic conceptions."
An influential Latin
translation of Sextus's "Outlines" was published by Henricus Stephanus
in 1562, and this was followed by a complete Latin Sextus with Gentian Hervet
as translator in 1569. Petrus and Jacobus Chouet published the Greek text for the first time in 1621. Stephanus did not publish it with his Latin translation either in 1562 or in 1569, nor was it published in the reprint of the latter in 1619.
Sextus's "Outlines" were widely read in Europe
during the 16th, 17th and 18th centuries, and had a profound impact on Michel de Montaigne
, David Hume
, and G.W.F. Hegel
, among many others. Another source for the circulation of Sextus's ideas was Bayle
. The legacy of Pyrrhonism is described in Richard Popkin
's The History of Skepticism from Erasmus to Descartes
and High Road to Pyrrhonism
. The transmission of Sextus's manuscripts through antiquity and the Middle Ages is reconstructed by Luciano Floridi
's Sextus Empiricus, The Recovery and Transmission of Pyrrhonism
Oxford: Oxford University Press
la:Liber:Sexti Empirici Adversus mathematicos, hoc est, adversus eos qui profitentur disciplinas, Gentiano Herveto Aurelio interprete, Parisiis, M. Javenem, 1569 (Vicifons).
- Sextus Empiricus, Against the Grammarians (Adversos Mathematicos I). David Blank (trans.) (Oxford: Clarendon Press, 1998). ISBN 0-19-824470-3.
- Sextus Empiricus, Against the Ethicists: (Adversus Mathematicos XI). Richard Bett (trans.) (Oxford: Clarendon Press, 2000). ISBN 0-19-825097-5
- Sextus Empiricus, Against the Logicians. Richard Bett (trans.) (Cambridge: Cambridge University Press, 2005). ISBN 0-521-53195-0
- Sextus Empiricus, Outlines of Scepticism. Julia Annas and Jonathan Barnes (trans.) (Cambridge: Cambridge University Press, 2nd ed. 2000). ISBN 0-521-77809-3
- Sextus Empiricus, Outlines of Pyrrhonism. R.G. Bury (trans.) (Buffalo: Prometheus Books, 1990). ISBN 0-87975-597-0
- Sextus Empiricus, Selections from the Major Writings on Skepticism Man and God. Sanford G. Etheridge (trans.) (Indianapolis: Hackett, 1985). ISBN 0-87220-006-X
- Sextus Empiricus, Sextus Empiricus I: Outlines of Pyrrhonism. R.G. Bury (trans.) (Cambridge, Mass.: Harvard University Press, 1933/2000). ISBN 0-674-99301-2
- Sextus Empiricus, Sextus Empiricus II: Against the Logicians. R.G. Bury (trans.) (Cambridge, Mass.: Harvard University Press, 1935/1997). ISBN 0-674-99321-7
- Sextus Empiricus, Sextus Empiricus III: Against the Physicists, Against The Ethicists. R.G. Bury (trans.) (Cambridge, Mass.: Harvard University Press, 1936/1997). ISBN 0-674-99344-6
- Sextus Empiricus, Sextus Empiricus IV: Against the Professors. R.G. Bury (trans.) (Cambridge, Mass.: Harvard University Press, 1949/2000). ISBN 0-674-99420-5
- Sextus Empiricus, The Skeptic Way: Sextus Empiricus's Outlines of Pyrrhonism. Benson Mates (trans.) (Oxford: Oxford University Press, 1996). ISBN 0-19-509213-9
- Annas, Julia and Barnes, Jonathan, The Modes of Scepticism: Ancient Texts and Modern Interpretations (Cambridge: Cambridge University Press, 1985). ISBN 0-521-27644-6
- Bett, Richard, Pyrrho, his antecedents, and his legacy (Oxford: Oxford University Press, 2000). ISBN 0-19-925661-6
- Brennan, Tad, Ethics and Epistemology in Sextus Empiricus (London: Garland, 1999). ISBN 0815336594
- Brochard, Les Sceptiques grecs (1887)
- Burnyeat, Myles & Frede, Michael The Original Sceptics: A Controversy (Indianapolis: Hackett, 1997). ISBN 0-87220-347-6
- Hankinson, R.J., The Skeptics (London: Routledge, 1998). ISBN 0-415-18446-0
- Jourdain, Sextus Empiricus (Paris, 1858)
- Mates, Benson. The Skeptic Way: Sextus Empiricus's Outlines of Pyrrhonism. (Oxford: Oxford University Press, 1996).
- Pappenheim, Lebensverholtnisse des Sextus Empiricus (Berlin, 1875)
- Popkin, Richard, The History of Scepticism: From Savonarola to Bayle (Oxford: Oxford University Press, 2003). ISBN 0-19-510768-3