Principal Doctrine 23:
If you dispute all evidence of sensation, you will have no standard of reference when you judge those sensations which you say are deceptive.
Principal Doctrine 24:
If you reject a particular sensation and do not distinguish opinions regarding unconfirmed things from what is actually present in our sensations, our feelings, and the confirmed apprehensions of the mind, you will throw all the other evidence of sensation into confusion through this groundless idea and thereby reject all possible criteria of judgment.
And if, on the other hand, when considering the ideas formulated in your opinions, you treat as valid both that which is awaiting confirmation and that which is not, you will not fail to be mistaken, for you will have retained the whole cause of dispute in every judgment regarding what is or is not correct.
Commentary
Today’s two Principal Doctrines focus on a core topic in epistemology: the appropriate attitude to take towards “sensation,” or the evidence of our physical senses. The Epicurean theory of knowledge is a large subject in itself, and not a main focus of this site, so I will not treat these two maxims as a springboard to launch into a comprehensive account of Epicurean epistemological theory. Instead, I think it is important to keep in mind their status as two entries in a series of forty otherwise entirely ethical maxims—they are not intended to present the full picture of Epicurean epistemology, but instead to make an essentially ethical point, one about how a person should choose to live. That advice boils down to this: don’t be a Skeptic.
(This is not to say that we should not be skeptical of bad arguments and unfounded beliefs. Epicurus puts a great deal of emphasis on rooting out “empty opinion” (kenai doxai) and so there is, in practice, a significant amount of agreement between ancient Skeptics and Epicureans, which I will explore further next week. But to elevate the withholding of belief to be the central tenet of one’s philosophy of life is unwarranted.)
The first of these maxims is quite straightforward:
PD 23: If you dispute all evidence of sensation, you will have no standard of reference when you judge those sensations which you say are deceptive.
The basic idea addressed here, not necessarily specific to one particular brand of Skepticism, is the contention that our senses can be deceptive. The go-to ancient examples included the observations that a partially submerged oar can appear to be bent, rather than straight, or that a square tower can appear to be round when viewed from a distance. Different philosophical schools could then take such claims in different directions: Academic Skeptics maintained that we should only treat our knowledge as “probable,” Pyrrhonists stressed that “appearances” were not the same as objective reality, and other thinkers generally downplayed the importance and validity of empirical observation compared to pure reasoning and dialectic.
In this maxim, Epicurus issues a fairly commonsense response to such Skepticism: if you want to claim that our senses are deceptive, then on what basis are you claiming their deceptiveness, if not through appeal to other senses? If you are asserting that the oar is in fact straight, presumably you are looking at it when not submerged, or perhaps you are touching it and evaluating it by feel. If you are asserting that the tower is square and not round, presumably you are looking at it from a closer distance. The conclusion “our senses are deceptive,” then, doesn’t seem quite right. The light waves are not “cheating” in one case, but then behaving “honestly” in another—the light waves are doing what they always do in similar circumstances, and we misinterpret them.
In Epicurean terminology, all sensations (aesthesis) are said to be “true” or “real” (alethes). Whether they unfailingly convey the right idea of reality to us depends on our interpretation and judgment, but the evidence of the senses themselves should not be thought of as “false.” To one who knows how light refraction in water works, the appearance of a bend in the half-submerged oar is normal and expected.
Still, if it is admitted that certain observations may lead our interpretations astray, how should we pursue the truth? Idealist philosophers use that “failing” of empirical observation as an excuse for denigrating all empirical research in favor of pure logic, dialectic, or metaphysical speculation. Skeptics use it as an excuse for questioning the possibility of true knowledge. Epicurus’ conclusion is more obvious, straightforward, and compatible with modern scientific method: if our observations are insufficient for reaching a clear understanding of something, we need to get better observations. The main way we can confirm or disconfirm the initial impressions from our sensory evidence is by collecting more evidence from our senses. If our initial observation is distorted or distant, we need to obtain sensory evidence that is clear (enarges) and close-up (paron, literally “present”). Pull the oar out of the water. Get closer to the tower. That’s what people living in the real world do.
Initial life advice, then, from this epistemological stance? Don’t abandon the gathering of empirical evidence as a means of pursuing the truth. Don’t abandon the concept of knowable truth just because you notice a mistaken judgment.
The second maxim elaborates and expands on this point:
PD 24: If you reject a particular sensation and do not distinguish opinion regarding unconfirmed things from what is actually present in our sensations, our feelings, and the confirmed apprehensions of the mind, you will throw all the other evidence of sensation into confusion through this groundless idea and thereby reject all possible criteria of judgment.
And if, on the other hand, when considering the ideas formulated in your opinions, you treat as valid both that which is awaiting confirmation and that which is not, you will not fail to be mistaken, for you will have retained the whole cause of dispute in every judgment regarding what is or is not correct.
Given the increase in technical jargon1, let’s start with a paraphrase of the main points of these two sentences:
If you reject a sensation (rather than distinguishing opinion as the source of error), you will be logically compelled to distrust all of the evidence of your senses, which would undermine any livable basis for knowledge and judgment about the world. Don’t reject sensation.
If you accept all of your opinions, both those which have been confirmed by careful, painstaking observation and those which are “awaiting confirmation”—i.e. those derived from distant, unclear, or haphazard observation—that would also be a mistake. Humans do make mistakes in interpreting sense-perceptions—you should still try to avoid interpretive errors.
The practical conclusion of what one should do when pursuing an accurate knowledge of the world is not explicitly spelled out here, but is pretty clearly implied by the two branches of this maxim: accept the truth and value of your sensations themselves, but seek confirmation when their initial reports are vague or incomplete.
I suspect a lot of philosophers will find this a pretty weak response to Skepticism. When a Skeptical philosopher says, “But look! our senses can deceive us!” they are rarely quieted by a pragmatic response of “Try to get a better look. Maybe get a little closer.” But for practical people interested in living effectively, Epicurus’ position is far more sensible than an across-the-board withholding of belief.
This greater practicality is obvious—whatever the Skeptics say, they all actually use the evidence of their senses to navigate the material world. And they will typically admit this, arguing that they are nonetheless making an important technical distinction about the reliability of knowledge. I’m not really convinced about this importance: at the end of the day, I think effectiveness in daily life is the most pertinent gauge of reliable knowledge. I’ve never personally found any supposed untrustworthiness of the senses to impinge upon my functioning in the world. To spend time denying the certainty of our clear perceptions (Academic Skeptics), or drawing distinctions between “appearances” and objective reality (Pyrrhonists), does not seem to me like a particularly fruitful form of philosophy.
Emerson said something similar about unhelpful occupation with the philosophical and theological conundrums of his day.
The intellectual life may be kept clean and healthful, if man will live the life of nature, and not import into his mind difficulties which are none of his. No man need be perplexed in his speculations. Let him do and say what strictly belongs to him, and, though very ignorant of books, his nature shall not yield him any intellectual obstructions and doubts. Our young people are diseased with the theological problems of original sin, origin of evil, predestination, and the like. These never presented a practical difficulty to any man, — never darkened across any man’s road, who did not go out of his way to seek them. (“Spiritual Laws”)
Epicurean philosophy is therapeutic. It promotes healthy thinking. The thinking of most non-philosophers has gone astray in one way or another, filled up with empty ideas that are often too distant from the real life of the senses, clear and simple concepts, and accurate comparison of the pleasures and pains of life. Many people think, for example, that pursuing fame is a high-probability path to happiness, or that death is a terrible thing.
Sometimes, however, the teachings of venerable religions or famous philosophers are also counterproductive when it comes to intellectual health and spiritual well-being. Idealists who teach the existence of vindictive gods or immaterial Forms are layering unnecessary and unhelpful fictions onto your understanding of the world. Similarly, Skeptics who inflate the proper puncturing of groundless beliefs into an all-encompassing outlook on life, in which our senses, pains, and pleasures are no longer to be believed, are similarly importing unnecessary difficulties and perplexity into the project of living well.
Read the complete series on the Principal Doctrines here.
Original Text
23. εἰ μαχῇ πάσαις ταῖς αἰσθήσεσιν, οὐχ ἕξεις οὐδʼ ἃς ἂν φῇς αὐτῶν διεψεῦσθαι πρὸς τί ποιούμενος τὴν ἀγωγὴν κρίνῃς.
24. εἰ τινʼ ἐκβαλεῖς ἁπλῶς αἴσθησιν καὶ μὴ διαιρήσεις τὸ δοξαζόμενον κατὰ τὸ προσμένον καὶ τὸ παρὸν ἤδη κατὰ τὴν αἴσθησιν καὶ τὰ πάθη καὶ πᾶσαν φανταστικὴν ἐπιβολὴν τῆς διανοίας, συνταράξεις καὶ τὰς λοιπὰς αἰσθήσεις τῇ ματαίῳ δόξῃ, ὥστε τὸ κριτήριον ἅπαν ἐκβαλεῖς·
εἰ δὲ βεβαιώσεις καὶ τὸ προσμένον ἅπαν ἐν ταῖς δοξαστικαῖς ἐννοίαις καὶ τὸ μὴ τὴν ἐπιμαρτύρησιν, οὐκ ἐκλείψεις τὸ διεψευσμένον, ὡς τετηρηκὼς ἔσει πᾶσαν ἀμφισβήτησιν κατὰ πᾶσαν κρίσιν τοῦ ὀρθῶς ἢ μὴ ὀρθῶς.
If you really want to know:
“That which is awaiting confirmation,” or simply “unconfirmed things” (to prosmenon ten epimarturesin): Initial impressions from the senses to which we are not yet prepared to give full assent, pending validation by more proximate and unambiguous observations.
“The feelings” (ta pathe): Our feelings of pleasure and pain are considered part of the Epicurean epistemological canon (along with sensation and general concepts). We do not need any further evidence to say that we find something painful (which is not to say that we will not make errors in calculating our future pain and pleasure, which can influence our estimate of the total net pleasurability of a current activity or situation).
“Apprehension of the mind” (epibolen tes dianoias): This is a tricky one. Cyril Bailey dedicates a 15-page appendix to trying to understand this phrase in his Epicurus: The Extant Remains (1926). In general, an epibolen is an apprehension or view of something that we attain after we give it our focused attention. You can have an epibolen of the senses; Bailey considers this the equivalent of looking at something or listening to something, rather than passively seeing or hearing in general. An epibolen tes dianoias (tes dianoias = of the mind) is apparently intended as a kind of cognitive process that is more reliable than random, ungrounded opinions. Bailey glosses it as “the apprehension of a scientifically verified concept” (274). Such apprehensions are not officially part of the Epicurean canon, but they are pretty close.
“Confirmed” (phantastiken) apprehension of the mind: Bailey treats phantastiken as not strictly necessary and adding nothing to Epicurus’ usual use of “apprehension of the mind,” but Norman DeWitt notes that—despite the English derivatives like “fantasy”—Epicurus uses this word specifically to denote things that are objectively true. DeWitt’s preferred translation is therefore “immediate” as opposed to “remote” (Epicurus and His Philosophy, 138).
This is all disputed stuff and absolutely perfect translations are difficult. I basically accept the point that “fantastic” means “real,” but suggest something of Bailey’s “scientifically-verified” by my more compact rendering of “confirmed.”
Oh, where to even begin. I was sincerely hoping you'd try to tackle this one.
The bent oar and the tower have to be some of the oldest, most cliché examples in the whole tradition at this point, definitely fossils. What if we used a modern example to distinguish between the evident and non-evident instead? Take eyewitness testimony research, people who confidently remember seeing things that were never there, or have their memory of an event reshaped just by being asked a leading question afterward. That's the evident/non-evident line in practice. What someone actually perceives in the moment is one thing, the confident story built on top of it afterward is something else entirely, and decades of courtroom cases have shown us how badly the two get confused.
I've also noticed you're treating Academic Skeptics and Pyrrhonists as basically the same target here, but they're pretty different schools with pretty different mechanisms. It'd be a bit like comparing Epicureans with Cyrenaics, both get called hedonists, but one's chasing immediate bodily pleasure and the other's calculating long-term absence of pain. I wonder, is Pyrrhonism even the right word to file under Skeptic in the sense you mean it in this essay, or is that just lumping two things that don't actually belong in the same box, to make a quicker point?
I think if we’re going to talk about the Principle Doctrines, then we should assume that they written by Epicurus, and that puts a date range on them, in which case the Skeptical Academy is in the future. It also means Epicurus’ target was early Pyrrhonism, about which we know little - just a few quotes from Timon. There’s a range of thinking about the degree to which the Pyrrhonism that we know from Sextus Empiricus and Diogenese Laertius reflects the Pyrrhonism of Pyrrho. One end of the range is that there’s only modest resemblance and that Pyrrhonism as we know it was largely invented by Aenesidemus, who made Pyrrho a figurehead. The other end of the range is that it is an evolved and elaborated version of Pyrrho’s teachings. In either case, we can’t be sure whether Epicurus’ target was something different from the Pyrrhonism we know now. In particular, comparing the Aristocles Passage with Sextan Pyrrhonism, there’s a difference between the two, and the applibity of these two Principle Doctrine differs between them, as well.
PD 23 (If you dispute all evidence of sensation, you will have no standard of reference when you judge those sensations which you say are deceptive.) is easy to address. All sensation is relative. Sensation can be compared with other sensations, particularly those from advantageous positions, as a standard of reference. This is obvious, straightforward, and compatible with modern scientific methods: if a particular observation is in doubt, it can be referenced against other observations to see if they provide disconfirming evidence.
PD 24 doesn’t seem applicable to Pyrrhonism. The first part of PD 24 looks to me like a critique of Platonism, as Platonism rejects the senses in favor of the Forms (e.g., Allegory of the Cave). Pyrrhonism, however, accepts the senses and rejects non-evident stuff like the Forms. The acceptance does come with reservations about the validity of the senses, but otherwise it’s not much different from the Epicurean approach.
It seems to me that your real concern is about what you infer about the Pyrrhonists. Consider this statement:
“Skeptics who inflate the proper puncturing of groundless beliefs into an all-encompassing outlook on life, in which our senses, pains, and pleasures are no longer to be believed, are similarly importing unnecessary difficulties and perplexity into the project of living well.”
Saying that these things “are no longer to be believed” does not accurately represent what Pyrrhonists are doing. It goes much too far. It positions these things as irrelevant. That’s simply not the case. All we’re saying is that one should not be confident that they accurately represent reality; meanwhile, despite that caveat, they’re all we have to go on.