Sextus Empiricus was almost certainly, as his name suggests, a doctor of the empiricist school, which flourished from the third century BCE until at least the third century CE. His dates are very uncertain, but he probably lived and worked, perhaps in Rome, sometime early in the third century CE.
He is mentioned as a prominent skeptic in Diogenes Laertius’s Lives of the Philosophers (DL) 9.116, written probably in the third century; but the men Diogenes names as his teacher and pupil, Herodotus of Tarsus and Saturninus, are even more obscure. He was certainly known as the authoritative source of skeptical argument a century later, when Saint Gregory of Nazianzus blamed him for the “vile and malignant disease” of arguing both sides of a question that was infecting the church.
How original he was is unclear—it is hard to tell partly because our other sources for skepticism are so exiguous—but he seems to have been more of a compiler than an original thinker; and in any case it is to his preservation of a large body of skeptical argumentation, whatever its provenance, that his importance in the history of philosophy is due.
|Outlines of Pyrrhonism|
His best-known work is Outlines of Pyrrhonism (PH), a digest of the arguments and general strategy of that version of skepticism named for Pyrrho of Elis. The precise relationship between the position outlined by Sextus and that of Pyrrho is unclear—Sextus himself says that his philosophy is called “Pyrrhonism” because “he seems to have applied himself to skepticism more thoroughly and conspicuously than any of his predecessors” (PH 1.7). PH summarizes what Sextus presents at much greater length in another work that also survives, at least in part.
This consists of the five surviving books generally (if misleadingly) known as Against the Professors (M) 7–11, subdivided as Against the Logicians (M 7–8), Against the Physicists (M 9–10), and Against the Ethicists (M 11). M 7–8 corresponds roughly to an expanded version of PH 2, while M 9–11 is summarized in PH 3. Whatever answered to the general treatment of skepticism in PH 1 is lost.
The texts known as M 1–6 form a different treatise, written with a rather different aim, consisting of a series of essays directed against the practices (and practitioners) of six of the seven “liberal arts,” in order, grammar, rhetoric, arithmetic, geometry, astrology, and music. Sextus also tells us that he wrote medical texts as well, but these are lost.
Book 1 of PH presents a general account of skeptical practice. Sextus is careful to avoid any suggestion that what he is presenting is a doctrine, or anything else with uncomfortably Dogmatic overtones. “Dogmatist”was the general name given by skeptics to their opponents who held positive, or even negative, views (the term also functions as an umbrella term to describe theoretically minded, as opposed to empirical, doctors; and was probably borrowed from medical terminology).
At the beginning of PH, Sextus presents skeptics as starting out from the same position as all other inquirers: They seek to assuage their disquiet by finding out the truth about things. But in any search there are three possible outcomes: one may (a) claim that one has found what one was looking for; (b) deny that it can be found, saying that it is inapprehensible; or (c) simply keep on searching. Option (a) is the position of the Dogmatists (Stoics, Epicureans, Platonists, and Aristotelians).
Option (b) Sextus ascribes to the Academic skeptics, claiming (controversially) that they positively deny that things are apprehensible (in the sense of certainly knowable) as to their actual natures, while also claiming that certain positions, in regard to both factual and evaluative matters are “more plausible” than others (PH 1 236–241); and both of these positions are unacceptably Dogmatic from a Sextan perspective.
Moreover, even though both schools report that epoche (suspension of judgment) regarding things that are naturally nonevident is the natural conclusion of the inquiry, the Academics present this as a goal, and as a good thing, whereas the Pyrrhonist has no attitude to it at all—it is simply something that happens, although it seems to bring tranquility (the acquisition of which was the initial object of the search) in its train. The Pyrrhonist follows option (c), and keeps on inquiring, following the appearances, but suspending judgment about what, if anything, might lie behind them.
Sextus is acutely aware of the dangers of incoherence involved in this presentation of a life without commitment—he cannot consistently recommend it (since that would involve supposing it to be objectively good, or at least choiceworthy); and he cannot claim that, as a matter of fact, following it will have the desired therapeutic effect of removing anxiety.
But he can (undogmatically) report his own experiences; it seems to him that this is how things have gone. Moreover, he is moved (so he tells us) by benevolence: Seeing the Dogmatists suffering from their vain pretensions to knowledge, he seeks to cure them, not because he positively affirms that it is good to do so, but simply because he finds himself so moved.
In the same vein, skeptics adhere (undogmatically) to “a quadripartite practice of ordinary life,” since “we cannot remain wholly inactive”: they follow “the guidance of nature, the constraint of the affections, the tradition of laws and customs, and the instruction of the arts”. The skeptic has a “criterion of action”—the appearances—but no “criterion of truth”. Sextus thus shows himself sensitive to the sort of objection made famous by David Hume, but anticipated in the Greek tradition, that skepticism is fatal.
PH 1.31–163 presents a version of the Ten Modes of Aenesidemus, but in a manner that betrays the later influence of Agrippa. The Modes are collections of considerations designed to (or rather, which have been found to) induce epoche on all nonphenomenal matters (the causal language is important: there can be no inference as such for the Pyrrhonist).
They consist in the collection of “oppositions”—Sextus describes skepticism as “a capacity for oppositions”: PH 1.8—cases where (apparently) x appears F to y (or in circumstances C), but not-F to z (or in circumstances C*); since there can be no nonquestion-begging way of deciding on the superiority of any one of the opposed appearances over any other (that is, we have no criterion) “we are moved to suspend judgment”.
The skeptic will adduce considerations on both sides of any question to promote “equipoise of argument”, not in order to support or undermine one side or the other. If you claim p, skeptics will adduce reasons why not-p, not because they believe them in propria persona, but simply because their benevolence compels them to. All skeptical argument is dialectical.
Thus when Sextus produces arguments against proof, he does so not because he believes, inconsistently, in the capacity of proof, as the Dogmatists allege; rather it is the Dogmatists who, insofar as they believe the canons of rational argument, must find those canons undermined from within. The skeptic has no beliefs about them at all. And it is in this manner that Sextus deploys the vast bulk of his argumentation in PH 2–3 and M 7–11, for and against particular philosophical and scientific positions.
In a similar vein, Sextus discusses the “skeptical slogans,” such as “no more [so than not so],” ouden mallon. The phrase ouden mallon had been used by earlier philosophers (including Democritus, Plato, Protagoras, and Pyrrho), but to signal, non-skeptically, that some things really were no more F than not-F.For the skeptic, it functions simply as a marker of a refusal to say, one way or another.
Equally, when skeptics say “I determine nothing,” or “all things are undetermined” (PH 1.197–199), they do not assert that nothing is determinable; these are merely expressions of how things seem. Indeed, the skeptical slogans apply to themselves: skeptics determine nothing, not even that they determine nothing (PH 1.206–209); here again they can avoid the charge of “negative Dogmatism” (option (b) above) they level at the Academics.
At PH 1.210–241, Sextus seeks to distinguish Pyrrhonism from other superficially similar philosophies by stressing the fact that all of them slide into Dogmatism. Thus Pyrrhonism is not relativism, at least if that positively affirms that everything is relative; the Pyrrhonist appeals to the relativity of appearances, but draws no ontological conclusion therefrom. Curiously, Sextus even distinguishes his practice from that of the empiricist doctors.
The latter follow the appearances; and make use of the type of sign (“commemorative”) that Sextus allows (PH 2.100–102), in which something evident is a sign of something else that is only temporarily nonevident, that is, whose existence can be confirmed by further investigation, as when smoke is a sign of (concealed) fire. (Sextus rejects “indicative signs,” whereby Dogmatists seek to infer to the hidden internal structures of things on the basis of evident phenomena, on the grounds that there can be no noncontroversial inference of such a kind: PH 2.104–133;M 8 199–300).
But they also developed a complex epistemology of reasonable expectation, based upon personal observation, reportage, and argument form analogy. And for Sextus, this strays too far toward a Dogmatic supposition that certain outcomes really are more likely than others. For this reason, he prefers the methodic school of medicine as a model, since this school also makes no affirmations, and simply follows the “quadripartite practice of ordinary life”.
In this vein, in M 1–6, Sextus allows that it is fine to practice some skill, as long as one does so undogmatically, that is without commitment to any supposed deep truths that the skill relies upon. This is the sense in which the skeptic may follow “the instruction of the arts,” and how Sextus may consistently be a (type of) doctor.