Daimôn (δαίμων): divine spirit within humans; our individual genius. Chrysippus held that a happy and well-flowing life was the result
“when the affairs of life are in every way tuned to the harmony between the individual divine spirit and the will of the director of the universe”
(Lives of the Eminent Philosophers 7.1.88). Epictetus tells us never to worry because we are never alone: God is always within, as is our
own daimôn (Discourses 1.14.14; not here).
Diairesis (διαίρεσις): analysis, division into parts. Used when distinguishing what is subject to our power of choice from what is not.
Dianoia (διανοία): thought, intelligence, purpose, faculty of mind. Haines notes: “not affected by the motions of the pneuma.”
Dikaiosunê (δικαιοσύνη): justice, righteousness. Diogenes Laertius noted that for the Stoics, it meant “being in harmony with the law and
tending to bring people together” (Lives of the Eminent Philosophers 7.99; not here). It is one of the four cardinal virtues (i.e., self-control,
justice, courage, and wisdom). The word is used seventeen times in Marcus, always in the spirit Diogenes Laertius outlines, where it appears
with the other virtues (see especially 3.6, 5.12, 7.63, and 12.15). Epictetus is notable in 3.1.6b–9, where he speaks of “the just” as the kind of
person we should strive to be.
Dogma (δόγμα): that which seems to one; opinion or belief; philosophically, dogmata are principles or judgments established by
reason and experience. Haines notes that “what the sensations are to the body and impulses to the soul, dogmata are to the intelligence.”
Epictetus takes aim at the untested form of dogmata by framing them as τὰ πονηρὰ δόγματα, or oppressive or worthless opinions that must
be rooted out by our reasoned choice (Discourses 3.3.18–19; see also 3.19.2–3) before they destroy our inner fortress (4.1.86). The term
appears more than one hundred times in Epictetus (see Enchiridion 5 , where he says that it’s not things that disturb us, but our
judgments/dogmata about them) and twenty-three times in Marcus (see especially 4.49, 7.2, 8.1, 8.22, and 8.47, where he often talks about
straightening out your principles). Marcus and Epictetus also use the word krima (κρῖμα) when talking about decisions and judgment (Marcus,
Meditations 11.11, 8.47; Epictetus, Discourses 4.11.7).
Dokimazein (δοκιμάζω): to assay; to put to the test; to thoroughly examine. This is a key verb in understanding Epictetus’s Stoicism
(found ten times in the Discourses and once in the opening of the Enchiridion), but it was not used by Marcus. The word carries the meaning
of the assayist, one who tests fine metals and coins to verify their authenticity. In one of the most memorable passages in Epictetus, he
compares our need to test impressions to what is done with coins and how the skilled merchant can hear a counterfeit coin cast upon a table
just as a musician would detect a sour note (Discourses 1.2.7–11ff). See also the exercises he gives for handling impressions (Discourses
2.18.24; Enchiridion 1.5). As sense impressions need to be put to the test, so too our judgments (dogmata/theôrêma) need a tough cross-
examination (ἐλέγχω; used by both Epictetus and Marcus) to be fully tested.
Doxa (δόξα): belief, opinion.
Ekklisis (ἔκκλισις): aversion; inclination away from a thing. The opposite of, but often appearing with, orexis. This is the first level of
self-coherence (see chart). Epictetus warns repeatedly that with aversions we must be careful to apply them only to our own concerns and not
to those controlled by others (see Discourses 4.1.81–82ff; not here). The word appears fifty-three times in the Discourses. In a vivid
metaphor of a sparring match, Marcus tells us we can avoid people who might have ill intent without being suspicious toward them (6.20). In
step with Epictetus, Marcus urges us to limit our aversion to only those things in our power (8.7). See orexis.
Ekpyrôsis (ἐκπύρωσις): cyclical conflagration (birth and rebirth) of the universe. This idea, central to Stoic physics and cosmology,
goes back to Heraclitus (Marcus 3.3; not here). Stoics equate this fire with the all-permeating reason (logos spermatikos) of the universe
(see Marcus 6.24).
Eleutheria (ἐλευθερία): freedom, liberty. The masses say that only the free can be educated, but the Stoic says that only the educated can
be free (Discourses 2.1.21–22). Including the adjectival form, it appears more than one hundred times in the Discourses. Marcus uses the
noun five times (see 5.9).
Eph’ hêmin (ἐφ’ ἡμῖν): what is up to us; what is in our control; our correct use of impressions, impulses, and judgments. The
Enchiridion (or Handbook) of Epictetus opens with this most famous of all Stoic phrases. Epictetus says when we want something outside
our control, we are stricken with anxiety (Discourses 2.13.1). Our judgments about what is up to us determine our freedom (3.26.34–35).
Epistêmê (ἐπιστήμη): certain and true knowledge, over and above that of katalêpsis.
Ethos (ἔθος): custom or habit. See also hexis. In late Stoic practice, there is a great focus on habit. Musonius Rufus’s ideas about education
were aimed at addressing the upbringing, environment, and habits that vary from person to person (Lectures 1.1). Epictetus carries this focus
on habit forward: “Since habit is such a powerful influence, and we’re used to pursuing our impulses to gain and avoid outside our own choice,
we should set a contrary habit against that, and where appearances are really slippery, use the counterforce of our training” (Discourses
3.12.6). He also talks about the importance of using a contrary, opposing habit in 1.27.4. The term appears seventeen times in Epictetus’s
Discourses. Marcus uses this term four times.
Eudaimonia (εὐδαιμονία): happiness, flourishing, well-being. Epictetus says that God made human beings to be happy and stable/serene
(εὐσταθεῖν/eustathein; Discourses 3.24.2b–3). Eudaimonia appears thirteen times in the Discourses and once in the Enchiridion. Epictetus
holds that it is incompatible with yearning for what we don’t have (Discourses 3.24.17). It appears twice in Marcus (7.67) in conjunction with
“life,” which, he says, depends on the fewest possible things (see also 7.17). Marcus has one other equivalent word in his use of
εὐζωήσεις/euzôêseis, or “happy in life” (3.12; none of these three reproduced here).