The grid of the "bare definition." The passage is the purest formula of the exercise of EXERCISEphysical definition (Hadot, définition physique): five questions that take any object apart down to its value-free composition. (1) "What is it in itself, in its own constitution (ἰδία κατασκευή)" — the thing without its social drapery. (2) "What is substantial and material in it" (οὐσιῶδες, ὑλικόν) — what it is made of. (3) "What is causal" (αἰτιῶδες) — the form, the shaping principle (the Stoic pair ὕλη/αἴτιον, matter and cause). (4) "What is it doing in the cosmos" (τί ποιεῖ ἐν τῷ κόσμῳ) — its function in the whole. (5) "How long does it subsist" (πόσον χρόνον ὑφίσταται) — its term.

Why this. Dividing a thing into stuff, cause, function, and span strips it of its irrational hold on the soul: what is dissected and dated does not enslave (cf. 8.3 — the philosophers "saw the things, the causes, and the matter"; 7.29 — δίελε καὶ μέρισον, "divide and part"). The fifth question brings in EXERCISEthe memory of finitude: everything "subsists" (ὑφίσταται) for a measured time only — the same thought of impermanence that runs through the book (8.6). No term-lemmata are in the text (οὐσιῶδες, ὑλικόν, αἰτιῶδες, κατασκευή are not carded); the exercise is definition, the governing discipline assent (to qualify the impression rightly), the sustaining one desire (to strip the thing of its value).