It is to be remembered that Lucretius had a very difficult task to perform—to expound a philosophical argument in a language which had not yet developed a philosophic vocabulary and, more over, to expound it in hexameter verse. He was himself acutely aware of the difficulty: i. 136 sqq., cf. i. 83o. The consequence is that he is compelled either to transliterate a Greek word, e.g., homoeomeria or to invent new words, e.g., adactus, variantia, differitas, formatura, tactilis, intactilis (= avacks), mactabilis, con ciliatus. It is probably due to the same cause that he uses corn pound adjectives with a facility and freedom which reminds us of Greek poetry—falcifer, florifer, squamiger, spumiger, fluctiva gus, velivolus, horrisonus. Doubtless based on Greek models is his extensive use of periphrastic expressions such as fida canum vis (vi. 1222 cf. Virg. A. iv. 132, odora canum vis), concharum genus (ii. 374), equorurn duellica proles (ii. 661), silvestria saecla ferarum (v. 967), and many others. Memmiades (i. 26) = Memmius seems in the same way to be copied from the Greek use of Otaoroons (Horn. Od. xi. 271, Il. xxiii. 679) =01.61..rovs.
Another characteristic which gives an archaic aspect to his poetry is the frequent use of alliterations, often with very happy effect, e.g., i. 72, Ergo vivida vis animi pervzcit et extra Processit longe flammantia moenia mundi, v. 1004. A peculiar form of alliteration is the combination of words derived from the same root, e.g., anxius angor (iii. 993), vel violenta viri vis (v. 961). Less notable is the repetition of the same word in a different case, e.g., Viva videns vivo sepeliri viscera busto.
His management of the hexameter metre is still somewhat tentative and unequal. As compared with the Virgilian hexameter, we note in particular the frequency of monosyllabic endings, e.g., so/is uti lux (iv. 198), per Veneris res (v. 848), and the use in any place in the line of words forming two feet, e.g., religionibus (i. 109), principiorum (i. praecipitavit (i. 251). In the mat ter of prosody he allows himself the utmost freedom. The same word is scanned now with one quantity, now with another, e.g., Crassaque conveniant liquidis et liquida crassis (iv. 12511; liquoris in v. 14, but liquor in i. 453 ; in i. 142 suddet is a disyllable, but in iv. 1157 sitadent is a trisyllable ; in vi. 963 dissoluit is a trisyllable, in vi. 446 a quadrisyllable. Similarly the scansion varies in words like diei, fidei, rei, illius, totius. Thus totius vi. 679, totius vi. 682 ; rei is a monosyllable in iii. 916, but a disyllable in ii. 548, vi. 919. Again suo is a monosyllable in i. 1022, V. 420, but elsewhere a disyllable. Such examples might be multiplied indefinitely. More remarkable perhaps are such unusual scan sions as glomere (i. 36o), vacillans (iii. 504), Brittannis (vi. '106), coruptunt (vi. 1135).
Unusual vocabulary, unusual prosody, awkward elision or hiatus, unnatural order of words (e.g., ii. 791 Nec quae nigra cluent de nigris sed variis ex) combine to give an uncouth aspect to the more argumentative portions of the poem. And it is to be remem bered that the De Rerum Natura is a didactic poem in the strict sense, a poem, that is to say, in which the teaching, the argument, is the chief thing, and the poetical form is rather introduced to commend the argument than the argument used as subsidiary to the poetical effect as, e.g., in the Georgics of Virgil. Lucretius sev eral times uses language which implies that he uses the poetical form to veil the asperity of his subject matter, e.g., i. 933.
The truest analogue to Lucretius's poem would probably be Paradise Lost. Milton is in general more akin perhaps in genius to Lucretius than any other poet that could be named. If the sheer poetic gift of Milton is the higher, as doubtless it is, yet he has a singular affinity with Lucretius in his combination of moral earnestness with a lively sense of the beauty of external nature, animate and inanimate. And in Lucretius, as in Paradise Lost, the sublimest passages of pure poetry are strictly germane to the argument of which they are the crown and complement.
In his greatest passages, such as the invocation to Venus which forms the prelude to the whole poem (i. 1-4o), the preludes to Books ii., iii., iv. and v., the remonstrance with the man who is afraid of death (iii. 892 sqq.), the progress of the seasons (v. 735 sqq.), the eulogy of Epicurus (i. 62 sqq.), the sacrifice of Iphi geneia (i. 8o sqq.), the cow sorrowing for her butchered calf (ii. 352 sqq.), and the like, he reaches heights hardly attained by any other Roman poet. Even the archaic tinge of style and diction seems but to lend such passages an austere dignity. If we seek further to inquire what is the secret of his power, we would find it not in any gift of memorable phrase—though he has memorable phrases enough—Medio de fonte leporurn surgit amari aliquid (iv. 1125), Suave mari magno (ii. I), Tantum religio potuit sua dere malorum (i. ioi)—but in his vivid imagination and conse quent power of sympathy. It is this warm sympathy which gives strength and meaning and persuasiveness to his message—that the natural needs of man in this life are few (ii. 20-33) and that death is not to be feared since it is for man the last end of all (iii. 910 sqq.). Did he preach this doctrine of the nothingness of death from a detached point of view, as of one who could himself and would have others "leave the warm precincts of the cheerful day Nor cast one longing lingering look behind," then his message would fall on deaf or unwilling ears among men of common human sympathies and emotions. It is precisely here that we find the secret of his power. Better aware than other men of the beauty of this earth—bird, beast and flower, river and sea, mountain and sky ; more than ordinarily alive to the joys of this life ; feel ing in all their fulness the nearness and dearness of family ties (iii. 892, lam iam non domes accipiet to laeta, nec uxor Optima nec dulces occurrent oscula nati Praeripere et tacita pectus dulce dine tangent), he would, not in contempt but in a large pity, persuade men that the cloud of mortality which overhangs them, darkening them even now with the anticipation of its terrors, holds at least no other evil than that it terminates this present life, and that there is only a dreamless sleep beyond the grave. Hence it is that he preaches the negation of immortality with all the fervour with which the Christian teacher preaches the immortal hope.