Lucretius III 417-444

418-830 serves as the third major division of the book. In these lines, Lucretius presents a series of proofs that the animus and anima are mortal. 

419: reperta < reperio (here "discoveries") stands in apposition to the indirect discourse of lines 417-18, itself dependant on noscere (418).   

420: tuā vitā is ablative following digna.   

421: fac authorizes a substantive clause of purpose of which the main verbs are subiungas and credas (423). The ut of the fully-elaborated clause has been, as often, suppressed, so fac and the present subjunctive work together to make a gentle command. utrumque < uterque "each" (the animus and anima, suggested by animos animasque (418) and the content of the book in general). Eorum is partitive genitive.   

422: animam is best understood to be in scare quotes. verbi causā "for example."   

423: mortalem esse: the subject is eam, suggested by animam (422). Animum is best understood to be in scare quotes.  

425-444: Given that the anima is much lighter and finer than water or smoke, which easily dissipate, its particles must likewise separate once the body is no longer intact. 

425: constare does not have an expressed subject (nor tenuem a noun to modify) until animam at 437. Lucretius can depend on the flow of the passage to ensure that the reader anticipates this subject, or retains res (424) as subject of discourse.   

430: imaginibus fumi nebulaeque movetur in book four, Lucretius explains that the imagines, thin films of atoms that fly away from physical bodies, contact our eyes, and thence the particles of our anima, causing us to see images of things. Quod genus "which (= "as") (is) the case" = "just like." Other examples of this usage in book three can be found at 221, 266, 276, and 327.   

432: altaria here may refer to the burning sacrifice itself, as opposed to the altar.   

433: procul dubio "of course" (lit. "far from doubt,") a phrase that Lucretius uses eight times. Nobis geruntur again alludes to the atomic mechanism of sight in Lucretius' system. Admittedly, this line could be puzzling to a reader unfamiliar with the theory.   

439: cum semel "as soon as."   

440: eius refers to the anima.   

443: quī "how," the interrogative adverb (quī) an old ablative of the relative pronoun. This is a common word in earlier Latin, but is found in Cicero as well. Credas is a potential subjunctive. Cohiberier = cohiberi. Cf. lines 67, 263, 623.   

444: corpore nostro: ablative of comparison. qui . . . sit: relative clause of characteristic. incohibens: belongs in the predicate "not restraining," "not having the power to contain." The in- is the privative prefix.