Genre and place in the book. The thirteenth passage is the first appearance of the concept of ὁ ἔνδον TERMδαίμων (the daimōn within) in Book II. By genre, a diagnostic sketch, dialectically arranged: first a diagnosis of an unhealthy state (ranging outside oneself), then a positive prescription (service to the inner daimōn), then a specification of that service (the triad of purity), and finally an ethical scale of relation to the gods, to human beings, and to those in ignorance. After 02-12, which set out a list of meditative prompts, 02-13 continues the analytic work: what it means to direct attention rightly.

Structure of the argument. Four movements.

1. Diagnosis of the error. Οὐδὲν ἀθλιώτερον — "nothing more wretched than" the person who wanders everywhere in circles, digs into "the depths beneath the earth" (the poetic citation), and tries to guess at the souls of others. This is a threefold enumeration of misdirected attention: outward (the world) — downward (the hidden) — sideward (the minds of others). All three are removed by a single move — the turn inward to one's own δαίμων.
2. Positive prescription. It is enough "to be with one's own inner TERMδαίμων alone, and to serve it (θεραπεύειν) sincerely." The word θεραπεία is Hadot's "care of the self" (Foucault: l'épimélie de soi) in its ancient form: that toward which philosophical activity is turned is not the world but an inner instance which calls for continuous cultivation. See also 02-08 (παρακολούθησις) and 02-06 (αἰδώς toward oneself).
3. The triad of purity. Θεραπεία consists in keeping the daimōn pure from three things:

• TERMπάθους — passion (the discipline of desire);
• εἰκαιότητος — rashness / randomness (the discipline of assent — precision of judgment);
• DOGMAδυσαρεστήσεως τῆς πρὸς τὰ ἐκ θεῶν καὶ ἀνθρώπων γινόμενα — discontent with what comes from gods and from human beings (the discipline of desire / action).

1. In Hadot's scheme this triad corresponds to all three disciplines at once (see 02-02): the daimōn is sullied along three different channels, and its service calls for three-sided work.
2. Triadic relation to the sources of what happens. In parallel, three dispositions toward those who act:

• Toward the gods — αἰδέσιμα (TERMreverence) δι' TERMἀρετήν (their excellence).
• Toward human beings — φίλα διὰ TERMσυγγένειαν (affection through rational kinship; see DOGMAoikeiosis).
• Toward those in ignorance — ἐλεεινὰ δι' TERMἄγνοιαν τῶν TERMἀγαθῶν καὶ TERMκακῶν (pity through ignorance of good and evil; an echo of the first passage 02-01).

The principal concept — ὁ ἔνδον δαίμων. Marcus's specific formulation: "the daimōn within oneself." Δαίμων here is not a low semi-divine power (as in popular religion) and not Socrates' warning δαιμόνιον (which was a voice from outside) but a functional synonym of ἡγεμονικόν / νοῦς / θεία ἀπομοῖρα — the rational divine part of the human being, localised within him as an inner guide. Epictetus' formula at Disc., book 2 (precise chapter to verify [verify:schenkl]): "you carry god within you and do not know it." Foucault in L'herméneutique du sujet (12 January 1982) notes that Marcus's formulation of ἔνδον δαίμων is a turning point in the ancient "care of the self": that of which the philosopher takes care is now genuinely interiorised.

The Pindar citation and its inversion of Plato. The phrase τὰ νέρθεν γᾶς ἐρευνῶντος (with the Doric γᾶς in place of Attic γῆς) is a Pindaric fragment, identifiable as fr. 292 SM (Snell-Maehler). The crucial point: the fragment has been preserved for us only through Plato — Theaet. 173e–174a, the famous "digression on the philosopher," where Socrates cites the poet with explicit attribution (κατὰ Πίνδαρον "τᾶς τε γᾶς ὑπένερθε"…). Plato is the only source through which we know this line of Pindar; Marcus is the second witness, after Plato, to the citation in ancient literature.

Decisively — Marcus inverts Plato's context. In Plato the citation works in praise of the philosopher: his free mind, not earthed in petty things, soars "beneath the earth and above the heavens" (τᾶς τε γᾶς ὑπένερθε … οὐρανοῦ θ' ὕπερ), measures all that is, and ignores what is near (εἰς τῶν ἐγγὺς οὐδὲν αὑτὴν συγκαθιεῖσα). Plato's philosophical cosmopolitan is the ideal, opposed to the earth-bound litigator who scrabbles among nearby affairs. In Marcus exactly the same portrait — the person who explores the underground depths and looks into the souls of his neighbours — becomes a diagnosis of wretchedness: οὐδὲν ἀθλιώτερον ("nothing is more wretched").

Moreover, Marcus makes a striking constructive move: he brings together two different Platonic oppositions — (a) the philosopher soaring up the heights and down the depths, and (b) the litigator-pettifogger digging into others' affairs — and qualifies both as one and the same error. In each case the gaze is directed outward (out, up, down, sideways), where it ought to be directed inward, to one's own δαίμων. What in Plato was the praise of the philosopher against the litigator becomes in Marcus a unified critique of both, in favour of a third mode — interiorisation.

This is not "polemic with Plato" in the sense of an explicit dispute, but a deep re-assembly of the Platonic topology of the philosophical life. In Plato the axis of the philosophical gaze is "above-below-around" (the universal vs. the near-at-hand); in Marcus it is "outer-inner" (out vs. in). For Marcus the underground depths and the heavenly heights are placed on a level with the souls of others: all three are equally external with respect to one's own ruling part. Foucault (L'herméneutique du sujet, lecture of 12 January 1982) treats this turn as a nodal moment in ancient interiorisation, where the care of the self for the first time receives the structure of a turn to the inner rather than to the cosmos or to one's neighbour.

A textual nuance: Marcus writes νέρθεν (where Plato transmits the Pindaric original as ὑπένερθε) — a lexical variation between two Doric adverbs, both meaning "from below / underneath." This indicates that Marcus is most likely citing from memory, not literally from the Platonic text — which agrees with the Meditations as the personal notebook of a philosopher rather than a formal treatise.

The triadic relation and the crossing with 02-01. The closing formula — "pity for them through ignorance of good and evil" — is almost a verbatim echo of the first passage of Book II (παρὰ τὴν TERMἄγνοιαν τῶν TERMἀγαθῶν καὶ TERMκακῶν). 02-01 stated it as the diagnosis for refusing anger at others; 02-13 repeats it — now as the third component of an emotional relation, alongside reverence toward the gods and love toward human beings. So Book II opens and almost closes (after 02-13 there is only 02-14, "even if you were to live three thousand years…," and the closing 02-17) with the same formula, forming a ring composition for the whole book.

The image of moral blindness. Πήρωσις is literally a "maiming." Marcus compares ἄγνοια τῶν ἀγαθῶν καὶ κακῶν to colour-blindness: "no smaller a maiming than the one that deprives one of the power to tell white from black." This is the harshest analogy of moral blindness in the Meditations: not "a tendency to err," not "inexperience," but a concrete sensory disability. The analogy works both ways: (a) ἄγνοια is a structural defect of perception, not a moral fault; (b) and therefore the right relation to such a person is pity (ἐλεεινά), not anger — just as one does not get angry at a colour-blind person. The analogy anticipates the late-antique Stoic (and Christian) view of sin as ignorance, calling not for punishment but for healing.

The disciplines. The principal one is desire: the triad of "purity from passion, rashness, discontent" is centred on the emotional disposition of the soul. The secondary is assent: "no rashness" (εἰκαιότητος) is the precision of evaluative judgment. The discipline of action is engaged through the triadic relation to others (the right address to gods, human beings, and those in ignorance).

Parallels. The theme of the inner δαίμων recurs constantly in Marcus: Med. 2.17 (the closing of Book II — also through the δαίμων); 3.4 (do not waste your life on what is another's); 3.5; 3.6; 3.7; 3.16 (philosophy = keeping the δαίμων pure); 5.10; 5.27 ("live with the gods; and he lives with the gods who … does all things by the will of the δαίμων that Zeus has given each as guardian and guide — and this is each person's intellect and Logos"); 7.17; 8.45; 12.3; 12.26. Epictetus on the personal δαίμων — Disc., books 1 and 2 (precise chapters to verify [verify:schenkl]). Stoic predecessor — Cleanthes (in SVF, vol. I; precise fragment to verify [verify:svf]). Poetic background — Pindar fr. 292 SM (see above) + Plato Theaet. 173e–174a + Tim. 90a–c.