Study Guide for the Epicurean Canon
There are three parts to Epicurean philosophy: the Canon (epistemology, or how we think about nature), Physics (the nature of things), and Ethics (art of living). The key premise behind the canon is that truth is possible and desirable, which refutes the radical claims of the Skeptics. If the attainment of truths is possible, then by what standards do we know them?
The Canon (the “measuring stick” or “standard” of truth) is our nature-given standard of truth and our connection with nature. It’s described as the Tripod of Truth because it stands on three legs, which represent different faculties: the five senses (hearing, touch, smell, taste, and sight), the feelings (also known as the hedonic tone, broadly categorized as varieties of pleasure and pain), and the prolepsis (also known as preconceptions, or anticipations, a conceptual faculty tied to speech and memory). Below are some key points on the canon.
Sources
Liber Qvartvs, the fourth book of De rerum natura, is our main extant source on the canon. It focuses on the importance of trusting and correctly using our faculties.
Kyriai Doxai 22-25 are the other main source for our canonics, as well as Philodemus’ “Methods of inference”.
If you fight against all your perceptions, you will have nothing to refer to in judging those which you declare to be false. - Principal Doctrine 23
If you reject absolutely any single sensation without stopping to discriminate with respect to that which awaits confirmation between matter of opinion and that which is already present, whether in sensation or in feelings or in preconception of the mind, you will throw into confusion even the rest of your sensations by your groundless belief and so you will be rejecting the standard of truth altogether. If in your ideas based upon opinion you hastily affirm as true all that awaits confirmation as well as that which does not, you will not escape error, as you will be maintaining complete ambiguity whenever it is a case of judging between right and wrong opinion. - Principal Doctrine 24
Canon furnishes raw data with no opinion added
All the faculties in the canon are pre-rational. They furnish raw data from nature with no opinion added. In every deliberation, we refer to the evidence of nature. Because this data is empirical, it’s not a point of dispute. Errors take place when we add opinion, or when we apply faulty reasoning instead of empirical reasoning (epilogismos).
On the independent authority of each faculty
Each faculty has sole jurisdiction over some aspect of our connection with reality. Only ears can report noise vibrations. Only smell can report chemicals and aromas wafting in the environment. Only eyes can report sights or photon particles. Only the pleasure and pain faculty can report what is choice-worthy and avoidance-worthy. This is because there’s no common object of perception about which different faculties would disagree. Therefore, each faculty has independent authority.
Enargeia of hedonic tone
Pleasure is satisfying and ergo choice-worthy for its own sake, and pain is repellent and ergo avoidance-worthy. These truths are directly experienced and self-evident, and require no arguments or logic. The Hegemon (like Aristippus before him) refused to argue about pleasure and pain, saying that these are nature-given faculties that receive raw data from nature, and not subject to logical formulas or arguments.
Prolepsis
While sensations tell us that something exists, they do not tell us what it is. For that cognitive process, we must rely on a faculty tied to both language and memory. The faculty of prolepsis helps us to recognize abstractions and things previously apprehended. The initial attestation and thought-object (to proton ennoema) serves to furnish an empirical source that justifies the place of this faculty within the canon. Without this faculty, we would not be able to clearly conceive the things that we give names to, and so it’s tied to the criterion of conceivability.
Epilogismos
You must reflect on the fundamental goal and everything that is clear, to which opinions are referred; if you do not, all will be full of trouble and confusion. - Principal Doctrine 22
In On Nature, the Hegemon said: “One must rely on sharpness of perception to separate the notions of nature from those that are designed with difficulty or obscurity … Pay full attention to the power of empirical reasoning (epilogismos).”
Epilogismos generally translates as “empirical or pragmatic thinking”, and Enargeia usually translates as clarity, or unmediated perception. More on this in the essay Enargeia and Epilogismos.
On clear speech
Concerning Epicurus’ clarity of speech, Laertius reported that Epicurus was so lucid a writer that in his work “On Rhetoric” he made clarity the sole requisite.
Obscurity is of two kinds: intentional and unintentional. It is intentional when one has nothing to say and conceals the poverty of his thought by obscure language that he may seem to say something useful. Connected with this is the use of many digressions, poetic images, recondite allusions and archaic language. Solecisms prevent the hearer from understanding many things. Only the true philosopher is free from these faults. - Philodemus, on Obscurity (from his Rhetorica)
In the same work, Philodemus says concerning using ordinary speech
One should use ordinary expressions appropriately, and not express oneself inaccurately, nor vaguely, nor use expressions with double meaning.
Conceivability
In order to refer to something, we must first clearly conceive it. Since it is easy to clearly conceive things for which there is evidence and impossible to clearly conceive of things that contradict evidence, we appeal to common sense by citing the criterion of conceivability.
Let us consider examples of the inconceivable. It's inconceivable that a man may be immortal because all men who existed in the past have died and there are no known and empirically verified cases to the contrary, and so it's fair to expect that all men living today will also die. We may call this “the argument of no known exceptions” (as Philodemus says: “with no case drawing us to the contrary”).
It's also inconceivable that a tree may ever have lungs or a nose, or grow hair or feathers, because never in our experience have we seen this.
The process by which an opinion concerning something imperceptible undergoes a conceivability test is known as a conceptual process, and in this process the prolepsis of play behavior, fantasy, and fiction must be distinguished from how we conceive of factual claims.
Opinions may be true or false
Sextus Empiricus reports that according to Epicurus, some opinions are true, some false. True opinions are those which are attested by and not contested by clear facts, while false opinions are those which are contested and not attested by clear facts.
Attestation and non-contestation are the criteria of something being true, while non-attestation and contestation are the criteria of it being false. And self-evidence is the foundation and basis of all four of these.
Attestation and non-attestation
Attestation is perception through a self-evident impression, that the object of opinion is such as it once was thought to be. Non-attestation is confirmation through self-evidence of the fact that the object of opinion is not such as it was believed to be. For example, if someone is approaching from far off, we conjecture, owing to the distance, that he is Plato. But when the distance is reduced, we recognize through self-evidence that it is not Plato. This sort of thing turns out to be non-attestation. If it had been confirmed that he is Plato, that would be attestation.
Non-contestation and contestation
Non-contestation is the conformity between a non-evident thing which is the object of speculation, and the opinion about what is apparent. For example, Epicurus, in saying that void exists, which is non-evident, confirms this through the self-evident fact of motion. For if void does not exist, there ought not be motion either, since the moving body would lack a place to pass into as a consequence of everything being full and solid. Therefore, the non-evident thing believed is not contradicted by that which is evident, since there is motion.
Contestation, on the other hand, is the elimination of that which is apparent by the positing of the non-evident thing. For example, the Stoic says that void does not exist, something non-evident; but once this denial is put forward, then that which is evident, namely motion, ought to be co-eliminated with it. For if void does not exist, then motion does not occur either, according to the method already demonstrated.
Our method of inference by analogy
It’s possible to infer about the non-evident based on that which is evident, that which has already been clearly perceived, but the things available for observation must be similar enough to the non-evident object of our investigation to warrant such inference by analogy.
Other schools objected to how Epicureans frequently draw generic non-evident conclusions from concrete, observed phenomena. Their arguments centered on how there are many unique cases and exceptions to things that are generally perceived. Our method has limited utility in cases that involve many unique exceptions, but general utility in cases that involve few or rare exceptions.
Aligning theory and practice
If at all critical times you do not connect each of your actions to the natural goal of life, but instead turn too soon to some other kind of goal in thinking whether to avoid or pursue something, then your thoughts and your actions will not be in harmony. - Principal Doctrine 25
Here, we find a concern with aligning theory or intellect (logos) and practice (praxeis). Furthermore, learning this Doctrine provides us with a tool for refuting impractical thinkers, and impractical thinking processes. The Hegemon in his Epistle to Herodotus says that what conflicts with experience must be false.
Colotes said universal epoché (suspension of belief) makes it impossible to live, which makes radical Skepticism impossible to practice. This is known as the apraxia (non-practicability) argument. Epoché is useful only with regards to that which awaits confirmation.
On how to think empirically concerning action and theory
Epicurus says that we think empirically concerning the actions based on the results observed from any course of action.
Concerning theories that do not seem to have empirical basis, they can be destroyed if they are false (whether rational or not), either if some other theoretical view based on it is false, or if when we establish a link with the action, this proves to be disadvantageous. If any of these things happen, it will be easy to conclude that theoretical arguments are false.
As for opinions which do not concern action, the cause of their error may be irrational or rational. These will be confuted as false if some non-theoretical opinion expressed based on it is untrue, or--if they become indirectly linked with action--wherever they lead to disadvantageous action. If none of these consequences ensues, it will be correct to conclude that opinions are true.
Method of multiple explanations
It’s possible that many theories concerning a particular phenomenon are simultaneously valid, so long as they do not contradict evidence or each other.
Diogenes of Oenoanda says: If one is investigating things that are not directly perceptible, and if one sees that several explanations are possible, it is reckless to make a dogmatic pronouncement concerning any single one; such a procedure is characteristic of a seer rather than a wise man. It is correct, however, to say that, while all explanations are possible, this one is more plausible than that one. You may read more about the method of multiple explanations here.
The rules for innovation
Epicurus gave two criteria for doctrinal innovation. Akolouthos (which translates as “following, next, as follows”) translates as internal coherence. The other criterion is symphonia, which may translate as consistency, and means that the innovation must have external harmony with the rest of our empirically-based opinions.
Comparison with Other Canons
The Epicureans are not the only ones who have a Canon, and comparing the Epicurean standards to those of other schools might furnish helpful insights to students. Other philosophies, like the doctrine of Mozi, include different criteria for the truth. According to this IEP essay, Mozi’s standards of truth are:
Conformity to the will of heaven and spirits
Conformity to the teaching and practice of ancient sages and kings
Good consequences
Confirmation by testimony of the masses’ senses of sight and hearing
It quickly becomes obvious that the last two standards seem true and useful, but not the first two. Although it’s beyond the scope of this essay, it would be a good exercise to consider and place before our eyes case studies for each of these standards, to see if they are true, and to consider what disadvantages or uses they may bring.
We may also compare our method of inference by analogy with the Charvaka school’s rejection of this method, which in my view makes philosophy impractical, or at times difficult to practice. Charvakas (aka Lokayatas) are the Indian school of materialism. We will often not have all the necessary data needed to arrive at conclusions using empirical methods of inference. We must have methods to proceed in the absence of data. This results in a different version of the “apraxia” problem.
Conclusion
I have shared here a brief overview of most of the important points of the Epicurean canon that I’ve gathered over more than a decade of study, each of which offers thought-provoking conversation starters that take us down a different rabbit hole of philosophical study. For a long time, I have wanted to gather all these ideas in one place, in a single essay, for easy reference.
If you have questions, commentaries, or insights, or simply would like to study these points in greater depth, feel free to join us at the Garden of Epicurus FB group. Ancient Kathegemones always encouraged students to write outlines of what they were learning. You gain the most benefit if you ponder, gather and write your own thoughts and commentaries on these ideas and on the relevant PD’s and parts of De rervm natvra. Happy Eikas!
Further Study:
Essay: Enargeia and Epilogismos
Video: The Epicurean Canon
Essay: On methods of inference