## 1. Life



We know little about Lucretius' life beyond what we can infer
from his work. Our sole external reference comes from Cicero, in a
letter to his brother Quintus serving with Caesar in Gaul, dated from
February 54 BCE (*Q.F*. 2.10.3). Cicero agrees with his
brother's praise of the work, noting that it displays both
brilliance and originality, but also considerable craftsmanship.
Although Cicero and his brother may have read an earlier or partial
draft, such a date for the poem we have is compatible with two main
internal indicators.



First is the poem's addressee, the Roman aristocrat, Memmius,
named only in books 1, 2 and 5. While doubts are possible as to which
member of the Memmii Lucretius so honoured, most likely he is C.
Memmius, the praetor of 58 BCE, governor of Bithynia in 57, where the
poets Catullus and Cinna served on his staff, and who was exiled in 52
BCE as the result of an electoral scandal. The story, attested in
other letters of Cicero, that Memmius had plans to build on the site
of Epicurus' house (in Melite, not the Garden itself), has
sometimes been taken as spite from a failed attempt at conversion, but
it makes more sense as an offer of patronage by an Epicurean-Roman
grandee that fell afoul of local sensitivities (Morgan and Taylor
2017). The friendship with Memmius to which Lucretius aspires
(*DRN* 1.141) need not imply equal status for Lucretius but is
also compatible with a patronage relation. The second indicator is
Lucretius' mention at *DRN* 1.41 of the current age as
'this troubled time for our country'. The standard view,
that this relates to the early 50s was challenged by Hutchinson
(2001), who argued for 49-48 BCE, but for a rejoinder see Volk
(2010). Krebs (2013), in support of the earlier date, shows some
possible Lucretian influence on Caesar's vocabulary in his
*Commentaries on the Gallic War.*



Later biographical material contains a few plausible elements but is
otherwise unreliable. Donatus' life of Vergil claims that
Lucretius died on 15th October 53 BCE, the same day Vergil reached
manhood (donned his *toga virilis*). The date is possible, but
the coincidence is obviously a passing of the poetic torch. Jerome
gives his birth as 94 BCE and his death at age 44 or 39 (uncertain
text; 39 best matches other evidence), but then relates a bizarre
story that Lucretius was driven mad by a love potion and composed the
*DRN* during the 'intervals of sanity' before he
committed suicide. Thereafter Cicero edited or prepared the poem for
publication. That the love philtre was administered by his wife is not
in Jerome but turns up in medieval sources. Much of this is hard to
take at face value (Holford-Strevens 2002). Cicero's involvement
in the initial diffusion, as opposed to editing of the *DRN*,
is just possible, but he never mentions it in his later philosophical
works. Otherwise, Jerome's tale of madness does not square with
the earliest reception of the *DRN*, the high esteem shown
Lucretius in Vergil, Horace, Ovid and beyond.



To consider only the first of these, his influence on his younger
contemporary Vergil (70-19 BCE) was central. Vergil's
admiration is made quasi explicit in the poetic blessing at
*Georgics* 2.490-92: 'Happy he who was able to know
the causes of things and crushed underfoot all fear, inexorable fate,
and the harsh roar of greedy hell'. In specifying the basis for
this happiness, 'knowing the causes of things', Vergil
evokes Lucretius' title (*rerum causas* suggests
*rerum natura*), yet also connects this universal knowledge to
its practical aim: the banishment of fears of all kinds, including
liberation from fatalism (the swerve) and the fear of death and the
afterlife (Book 3). Peace of mind in the here and now, Greek
*ataraxia*, achieved through the study of Epicurean, atomic
physics, was the formal, therapeutic goal of Epicureanism.
Vergil's evocation thus knowingly sums up some of the
*DRN*'s key themes, and flatteringly conflates
Lucretius' poetic accomplishments with the wisdom of Epicurus
himself --flatteringly because in doctrinal matters Lucretius
only depicts himself as following his master. More importantly, the
beatitude Vergil attributes to him is hardly compatible with, and more
than enough to dispel, Jerome's suicidal madman.



Lucretius' insanity and miserable end in Jerome seem rather
motivated by early Christian hostility to the Epicurean denial of
providence (Lactantius, sometimes using Lucretius as a source for
Epicureanism, calls him 'mad'), perhaps overlaid upon some
now-lost poetic-fictional retribution for Lucretius' attack on
erotic love in the concluding sections of book 4, although that is
only a guess. But even if our sole biographical source is not
credible, its chronology remains compatible with our other
information, that is, a life span ranging from the mid-90s to mid-50s
BCE. Perhaps one last nugget of plausibility among the biographical
dross is that a premature death, as opposed to suicide, does seem
consistent with the unfinished status of the *DRN*.


## 2. The poem's structure and lack of final revision



The six books of the *DRN* display a clear architectural
design:


1. Atoms and void as the sole permanent entities
2. Atomic motion and atomic shapes; the properties of compounds
3. The nature and mortality of soul; curing the fear of death
4. Activities of the soul: sensation and thought, volition, dreams
and emotions
5. Our world: cosmology, origins of life, and history of
civilisation
6. Meteorological and terrestrial phenomena



The most obvious feature is the progression in scale of the
subject-matter, in two-book increments. We start with the atomic level
in books 1-2, move to the human scale in books 3 and 4, and then
onto the cosmic in 5-6. Between each of the three pairs the
first book concentrates on the nature or permanent properties of the
subject, while the second depicts its powers and activity, the subject
in action. Only the atoms, however, are indestructible and thus
everlasting. All generated entities, from our souls to the cosmos, are
compounds and so transient and destructible (on gods see section 7
below).



A second structuring feature is the direction given by the themes of
birth and death. The opening hymn to Roman Venus features a spring
scene of birth and joy, nature at her most benign and nurturing, while
books 3 and 6 close on the theme of death. Book 3 argues for the
mortality of the soul, and its final sections seek to remove the fear
of death, while Book 6 ends with a dark and horrible portrayal of mass
death adapted from Thucydides' account of the Athenian plague in
430-426 BCE. A balance between the two halves of the work is
also marked out by the one and only mention of Epicurus by name in the
whole *DRN*, at 3.1042. This unique direct mention is already
conspicuous, but its position at the end of book 3, at the very core
of the poem, gives it more prominence.



Such large-scale symmetries show careful poetic design. At the same
time, there are a number of indications that the *DRN* is
lacking its final revision. The strongest sign of this is a passage
from the opening of Book 4. Lines 4.45-53 recap the contents of
books 1 and 2 and then announce as the next subject
*simulacra*, Lucretius' renderings of the
*eidola*, the thin film of images constantly shed by all solid
objects, whose stream is the object of vision. These are indeed
treated next but, oddly 4.45-53 make no mention of the soul, the
topic of book 3. Worse, the lines follow another programmatic passage,
4.26-44 also introducing the *simulacra*, but now given
as the sequel to the discussion of soul. Together the two passages
show that 4.45-53 are a left-over from an earlier draft. This
relative imperfection, however, is also precious evidence for the
development of the work. As pointed out long ago (Mewaldt 1908), it is
evidence of a change of plan: at some point books 3 and 4 were
interchanged. Interestingly, this first ordering of the material
agrees with the order of exposition in Epicurus's *Letter to
Herodotus*.



A number of other features are less conclusive, but also suggest that
a final revision was never executed. First, Books 1 to 3 as a group
are shorter and more polished than 4 to 6. Second, the recurrence of
the vital honey and woodworm passage from book 1 at the opening of
book 4, with minor variations (1.926-950 = 4.1-25) is
awkward. Some suspect that the book 4 version was slated for
replacement, though some defend it. Third is the promise at 5.155 to
discuss the abodes of the gods at some length (*largo
sermone*), never taken up. Two final considerations, though
inconclusive, also deserve mention. For some, the ending of book 6 as
we have it is too bleak and lacking its moral, but others think it
adequate as a closure, the readers being by then sufficiently
instructed to draw the moral themselves. Lastly, the proems of books 1
to 3 appear to form an integrated pattern. The proems of 1 to 3 appear
to mark out degrees of cosmic ascent as equivalent to degrees of
Epicurean initiation: book 1 celebrates Venus/pleasure here on earth;
the second proem locates readers among 'the lofty sanctuaries of
the wise' (2.8), now free from the struggles of the
unenlightened; the third proem raises us all the way to the level of
gods (3.15-30), as if outside the cosmos. After that, however,
the pattern is harder to discern.]


## 3. Poetic format



Lucretius writes in Latin verse to spread the gospel of Epicurus, who
wrote in Greek prose two and a half centuries before him. A
preliminary review may best allow us to consider how Lucretius
adapted Epicurus' message to his own poetic medium and Roman
world. The present section covers poetic format, the next the
Epicurean background and sources. Some readers may prefer to skip
directly to section 5 on the contents of the *DRN* and read the
next two sections once they are more familiar with the poem.



Lucretius expounds his master's message in Latin hexameter,
adapting the inherited genre of didactic epic. Greek didactic epic,
which starts with Hesiod, standardly features a teacher offering
(fictional) live instruction on a given field of knowledge to a
student or addressee in need of such instruction. This continues to be
standard in Latin didactic (Volk 2002). In the *DRN*, Memmius,
standing in for the audience, is depicted as a beginner, which may not
have been the case. Lucretius is not the doctrinal, much less the
divine authority of the *DRN* -that is Epicurus, on both
counts- but he does actively instruct.



As his main Latin poetic influence, Lucretius adopts the archaic
format and diction of Ennius (239 -169 BCE), whose epic the
*Annales* on the history of Rome in 18 books, now known only
from fragments, was the Roman national epic until displaced by the
*Aeneid*. Couching his revolutionary message in this
established format may have helped Lucretius make it more acceptable
to his Roman audience and simultaneously prompt them to reflect
critically on traditional Roman values (Nethercut 2021). A second
important Latin influence appears to have been Cicero's
*Aratea* of c. 89 BCE, the orator's youthful rendering in
Latin verse of the first part of the *Phaenomena* by the
Hellenistic Greek poet Aratus (Gee 2013 chapters 3 and 4, and appendix
B for full parallels). The *Phaenomena*, published c. 276 BCE,
is a work on astronomy and weather-signs. As was widely recognised,
most of its subject-matter comes from the prose treatise of the same
name by the fourth-century mathematician and scientist Eudoxus of
Cnidus. One of the more popular poems of antiquity, the
*Phaenomena* was at the forefront of a trend in Hellenistic
didactic poetry, in which a poet could showcase his originality,
learnedness and virtuosity by taking on obscure or challenging
technical subjects. For Lucretius, since unobservable atoms and void,
the most obscure topics possible (DRN 1.933 *obscura de re*),
provide the subject-matter of the *DRN*, and given that
Epicurus wrote in a clear but often complex Greek prose saturated with
technical terms, on these two criteria it makes sense to view him as
an heir to the Hellenistic tradition of learned didactic (Kenney 1970,
Brown 1982, Gale 2007). To be sure, when at 1.921-30 Lucretius
advertises his originality as the first Latin poet to attempt his
subject, he tells us that he does so, at least in part, for 'the
high hope of renown'. This is not necessarily incompatible with
Epicureanism, though it hardly flows from it (on Epicurean poetics see
section 4). As for the challenge posed by Epicurean terminology,
Lucretius recognised it (1.136-9) and met it by opting, on the
whole, to avoid directly importing Greek technical terminology (Sedley
1998 ch. 2).



In a more important respect, however, the framework of Hellenistic
didactic epic is less helpful if it implies that Lucretius merely
*used* Epicureanism to generate some sublime poetry. On the
contrary, Lucretius' missionary fervour make it clear that the
medium serves the message and that the aim of the poem is to convert
the hearer to Epicureanism (Asmis 2016). This relation is most clearly
set out in the important 'honey and wormwood' passage,
from which I quote *DRN* 1.936-47:



> 
> But as with children, when physicians try to administer rank wormwood,
> they first touch the rims about the cups with the sweet yellow fluid
> of honey, that unthinking childhood be deluded as far as the lips, and
> meanwhile may drink up the bitter juice of the wormwood, and though
> beguiled be not betrayed, but rather by such means be restored and
> regain health, so now do I: since this doctrine commonly seems
> somewhat harsh to those who have not used it (*haec* *ratio
> plerumque videtur/ tritior esse quibus non est tractata)* and the
> people shrink back from it, I have chosen to set forth our doctrine to
> you in sweet-speaking Pierian song, and as it were to touch it with
> the Muses' delicious honey... . (transl. Rouse-Smith with
> modifications)
> 



Poetry sweetens the bitter medicine needed to restore the patient, so
that Lucretius subordinates his poetic activity, honey, to the cure
and salvation that is instruction in Epicureanism (for more on the
passage, Gale 2020). At the same time, this image of benevolent
deception is more complicated than it looks, since the medicine is not
actually bitter, it only 'seems' so to those who have not
experienced it. Indeed, no later than the opening of Book 3, Lucretius
depicts himself as a bee flitting through Epicurus' works,
feasting on the honey of his 'golden words' (3.13, fuller
quote in 4). The medicine has become the honey, it appears, at least
for those who have converted to Epicureanism.



The goal of philosophical conversion leads us to a last important
Greek poetic influence, the philosopher-poet Empedocles of Acragas
(490-430 BCE). Lucretius singles Empedocles out for explicit
praise at 1.729-33, even as he turns to criticize his elemental
theory from an atomist perspective. Empedocles was the father of Greek
four-element theories and was recognized as the canonical champion of
Greek philosophical didactic poetry. Although we know his work only
through fragments, the great number of identifiable allusions or
borrowings in the *DRN* from Empedocles, along with the
clustering of Empedoclean themes in the opening of Book 1, make it
clear that Lucretius was positioning himself as the Roman Empedocles
(Jobst 1907, Kranz 1944, Furley 1970, Sedley 1998, ch. 1).
Empedocles' goal was to convert the hearer to new
'scientific' understanding of the world. In one summing-up
passage, he explains how all things ('all that was, all that is,
and all that will be hereafter', a Homeric formula he adapts to
his own aims) are to be understood as the products of the four eternal
elements, earth, air, fire and water, acting under the alternating
influence of two moving-psychological powers, Love and Hate (*On
nature* 1.265-72 Laks Most 2016 D 73). This effectively
downgrades the world of experience to the rank of temporary products
of a more fundamental, invariant principles. Despite other important
differences, this is close enough to the atomist picture, both systems
being attempts to save appearances from the Eleatic challenge
(Mourelatos 1987; Wardie 1988; Burnyeat 2017). Empedocles was also
widely celebrated for his use of imagery. In particular, he pioneered
a new type of epic simile, one that displays multiple points of
correspondence between a given biological process and
-usually- a technological analogue. Lucretius' own
careful use of imagery and poetic vividness owe much to Empedocles
(West 1969, Schiesaro 1990, Garani 2007, Taylor 2020).



Since 1998, the Strasbourg papyrus, eds. Martin and Primavesi, has
shown that Empedocles' commitment to the afterlife of the soul
most likely stood alongside his scientific cosmology, not in
opposition to it. Although scholarship has only begun to reckon with
this new factor, it appears to make the new Empedocles even more
suitable as a Lucretian model (for a sketch of how this might have
worked, Trepanier 2007). The clearest instance of this
crossover between science and religion is section **d**
of the papyrus, where Empedocles loudly laments his meat-eating sins
even as he turns to describe the origins of living creatures from the
earth. This contrast in tones seems a plausible predecessor to
Lucretius' own two styles, the juxtaposition of cool technical
sections with impassioned rhetorical passages. Next, if more
controversially, the compresence in Empedocles of (Pythagorean?)
religion and Early Greek science suggests that the instruction itself
was framed as an 'assimilation to the divine'. That is, the scientific
quest for knowledge was understood as both natural and a form of
divinization for the pupil. This was an important theme in later
philosophy, Plato especially, but no less so in Epicureanism. In both
cases it also requires redefining the concept of divinity against more
popular inherited notions (see section 7).


## 4. Epicurean background



Epicurus (341-270 BCE), an Athenian citizen, began teaching and
amassing disciples in Mytilene on the isle of Lesbos and then at
Lampsacus on the coast of Asia Minor before establishing his school in
Athens in 306 BCE. In a property later known as the Garden, Epicurus
and his friends lived a closed community life devoted to philosophy,
in retreat from politics, and practiced an austere to ascetic
lifestyle. The latter was the case despite Epicureans'
commitment to hedonism (Tsouna, 2020). Outside accusations of hedonism
were thus strictly correct, but not sympathetic or informed. In
Athens, alongside his collaborators Metrodorus (331-278 BCE) and
Hermarchus, who succeeded him in 270 BCE, Epicurus continued to
produce instalments of his *On nature*, which eventually
totaled 37 volumes. The monumental *On nature* appears to have
been the foundational text for Epicureanism, so much so that school
members could make shorthand references among themselves to individual
book numbers, omitting the title (reconstruction in Sedley 1998 ch.
4). Even so, it was only one of many works produced by Epicurus and
the first generation of Epicureans, collectively referred to by later
Epicureans as 'the men' (Mitsis ed. 2020 has surveys
of all aspects of Epicureanism; on the life of the school,
see ch. 1 by Dorandi)



By the late Hellenistic period, the Garden was one of the four main
philosophical systems that competed for the allegiance of the educated
elite. Although all were originally headquartered in Athens, by the
first century BCE the schools had representatives and active branches
throughout the Mediterranean. In first-century Italy, the Epicureans
seems to have been especially successful in recruiting prominent
Romans, for example Atticus the banker, Cicero's friend and
correspondent, Cassius, the future assassin of Caesar, and
Caesar's father-in-law L. Calpurnius Piso Caesoninus. The last
of these was closely associated with or more likely the patron of
Philodemus of Gadara (c. 110-30 BCE), a prominent Epicurean
philosopher and accomplished poet, who taught in the area of the Bay
of Naples. The damaged and difficult-to-read carbonized papyrus rolls
first recovered in the 18th century at the Villa dei Papiri
in Herculaneum are to all appearances Philodemus' working
library. They include Philodemus' own philosophical works, some
drafts or teaching texts, a good number of classic Epicurean texts,
among which books from the *On nature*, sometimes in multiple
copies, a number of standard works from rival schools, and even a few
Latin manuscripts (Del Mastro 2014; Capasso 2020).



The Epicureans were noted for their doctrinal conservatism, with
orthodoxy controlled by appeal to the textual authority of the works
of 'the men' (Sedley 1989). Lucretius is in keeping with
this when he writes in the proem to book 3:



> 
> You I follow, O glory of the Graecian race, and now on the marks you
> have left I plant my own footsteps firm, not so much desiring to be
> your rival, as for love, because I yearn to copy you... You are
> our father, the discoverer of truths, you supply us a father's
> precepts from your scrolls, from your pages, illustrious man, as bees
> drink all they can in the flowery glades, so we likewise feed on your
> golden words, golden, ever most worthy of life eternal. (3.3-13
> Rouse-Smith transl. with modifications).
> 



As noted above, his own reverence for and enjoyment of these Greek
prose texts does not require the honey of poetic inducements, but to
Lucretius the Epicurean, they are all at once authoritative,
beneficial, and supremely enjoyable. It is worth noting, however, that
the order of comparisons made in the fuller passage, not quoted above,
rely on established poetic tropes used when a minor poet invokes the
example of a master (Volk 2002: 108-115). Lucretius therefore,
in the act of affirming his faith in Epicurus the philosopher,
retroactively casts Epicurus in the mold of a master poet. This shows
an active capacity to shape and color the material.



Despite such coloring, Lucretius makes it clear that he will not
deviate from his master's doctrinal path. Indeed, two of the
greatest peculiarities of the *DRN* relate directly to this
faithfulness. First, as best we can tell, Lucretius'
presentation of Epicurean physics is not 'live', in the
sense that it makes no attempt to update or defend the Epicurean
system in light of later scientific developments, for instance the
victory of 'head' over 'chest' as the seat of
the soul, thanks to the discovery of the nerves by Hellenistic doctors
(von Staden 1989, Leith 2020). Second and related to the first is the
absence of any explicit inter-school polemics, especially the kind one
would come to expect from reading the works of Philodemus or the
dialogues of Cicero. The main named philosophical adversaries in the
work are the three Presocratic philosophers deployed at
1.635-920 as the champions of alternative theories of matter.
Although it is tempting to infer that the various anti-teleological or
anti-providential critiques in the *DRN* are aimed at the
Stoics, Furley, in an influential (1966) article argued that in all
suggested instances the polemical targets are more likely Platonic or
Aristotelian (fullest reply in Schmidt 1990, with
counter-reply in Sedley 1998 ch 3). At most, the Stoics may
be included among the implicit targets of various anonymous views
criticised by Lucretius, but none of these are ever named. The closest
we get is an alleged Latin pun where, in calling the followers of
Heraclitus *stolidi*, 'stupid', some think
Lucretius is referring to *Stoici*, the Stoics (Bailey 1947
vol. II on 1.641 and 1.1068).



How should we understand this? Before considering some possible
answers, it will be useful to include two more factors: the question
of Lucretius' sources, and second, the school's views on
poetry.



The problem of Lucretius' sources is to a certain extent
academic since, as just seen, we can be confident that Lucretius
reproduces Epicurean doctrine faithfully. Despite that, and while also
recognizing that we only have access to a fraction of the material
that may have been available to Lucretius, a bit of stock-taking will
help clarify the background.



First, then, there is the material we possess. Thanks to Diogenes
Laertius' recycling of them into Book 10 of his *Lives of the
Philosophers*, we have three letters by Epicurus himself. These
are: the *Letter to Herodotus*: a brief summary of his physics;
the *Letter to Pythocles* on celestial phenomena, which
exemplifies the Epicurean use of multiple explanations for those
phenomena not open to closer examination*;* the *Letter to
Menoeceus*: a more basic introduction to his moral philosophy.
Beyond that, we have ancient collections of maxims culled from the
*corpus*, especially the *Key doctrines*, plus various
ancient reports, fragments and list of titles of lost works, to which
we can add the material from Herculaneum, which includes portions of
the different books *On nature* and those of other Epicureans,
Philodemus foremost. (The most up-to-date collection of all material,
with extensive notes, is the French translation by Delattre and
Pigeaud eds. 2010).



Among these sources, we can eliminate the *Letter to
Herodotus*, in other respects the most relevant extant text.
Lucretius cannot have relied on it, because the *DRN* is a
larger and more detailed treatment. Importantly, Lucretius' case
for atoms and void is the fuller one, designed for beginners.
Interestingly, though, as noted above, the *Letter*'s
order of exposition matches that of the *DRN*, or at least the
order we can discern before Lucretius changed the order of books
3 and 4. If we next consider the *On nature*, it will be
uncontroversial that it was in some sense Lucretius' ultimate
source, but also obvious that Lucretius will not have wanted to
reproduce all of its contents. In any case, the 37 books of *On
nature* were not a single continuous exposition, although certain
sections of it did function as sequential units.



Beyond that, the evidence is too complex for detailed examination, so
we can pass instead to scholarly theories. Over a century ago Giussani
(1896), followed by many, for example Bailey (1947 vol. I pp.
24-5), suggested that another known summary, the lost *Great
Epitome*, was Lucretius' main source. The appeal here is
that the putative source seems to be closer in scale to the
*DRN*, and possibly more suited to beginners, but other than
that there is very little to go on. Later in the 20th
century the trend was towards recognizing more Lucretian autonomy in
shaping and organizing the material (Clay 1983, Schrijvers 1999).
Against that, the most detailed investigation into this background so
far, Sedley 1998, argues that the first 15 books of the *On
nature* were Lucretius' main initial source, which he
gradually reshaped and compressed. Even for those who disagree with
its thesis, this study is the starting-point for subsequent
discussion, because it is the first to incorporate developments in
Herculaneum papyrology since the 1970s, importantly our improved
knowledge of the *On nature*, to which Sedley himself has
contributed significantly.



Since that study, the most significant development has been G.
Leone's magisterial (2012) edition of *On nature* II,
whose best-preserved sections deal with the Epicurean doctrine of the
*eidola*, the thin films of atoms emitted by all larger bodies
and which form the external basis of vision. On the one hand, the new
edition seems to reinforce Sedley's thesis, in so far as we can
now see that the order of exposition found in *On nature* II is
indeed reproduced both in the *Letter to Herodotus* and in
Lucretius. In the *Letter to* *Herodotus*, section 45 is
on infinite worlds, followed by sections 46-48 on the
*eidola*. In Leone's 2012 edition, columns 1-6,
though poorly preserved, clearly mention the infinity of atoms being
responsible for an infinity of worlds, *kosmoi*. Then, although
we lack textual evidence for a transition, what remains of the next
114 columns deal with the *eidola*. In Lucretius, provided we
factor in the swap of books 3 and 4, we have the same sequence: after
the conclusion of *DRN* 2 on infinite worlds, the
*simulacra* are dealt with at *DRN* 4.54-216 (=
book 3 in the earlier draft). On the other hand, and somewhat
bafflingly, this makes it more difficult to imagine the contents of
*On nature* I, since that single book now seems insufficient to
cover all the material abridged into *Herodotus* sections
37-44. For that reason, Sedley had argued that the
*eidola* section of Book 2 must have covered no more than a
fifth of that book (1998 p. 112). But Leone's edition suggests
something more like four fifths.



From sources let us now consider one final peculiarity of the
*DRN*, the apparent clash between the project itself, a
didactic poem on Epicurean physics, and the reported hostility to
poetry in Epicureanism. This topic has been much discussed, but it is
possible to think that its paradox has been overplayed, especially in
earlier scholarship (start rather at Obbink ed. 1995; full survey in
McOsker 2020). Epicurus is indeed reported to have been critical of
poetry, perhaps not specifically relating to verse itself, but as part
of the broader Epicurean rejection of conventional ideas and the
central role played by poetry in ancient education. So far, this is
merely the 'ancient quarrel between poetry and philosophy'
(*Republic* 607b5-6) with an Epicurean twist. More
narrowly, Epicureans' hostility to verse may have been sharpened
by the wish to demarcate themselves from the early Stoics'
embrace of poetry as making a positive contribution to elevated or
sublime content. Philodemus, in order to record his contempt for the
view, reports that the Stoic Diogenes of Babylon reported that the
earlier Stoic Cleanthes claimed: 'meters, melodies, and rhythms
approach as closely as possible to the truth of the contemplation
(theorias) of divine things
(theion)' (Philodemus *On
Music* 4, ed. Delattre 142.5-22; discussion in Asmis 2017).
We also have reports of Epicurean arguments criticising the use of
verse as not adding anything to the content. That is, Epicureans held
that the arguments and doctrines were what helped us achieve peace of
mind, *ataraxia*, and literary format does not contribute
anything to that (Sextus Empiricus *Adv. Math*. 1.299). Closer
to Lucretius, there is the case of Philodemus, who wrote extensively
on poetics and rhetoric and was himself an accomplished poet. The fact
that Philodemus was a poet makes a complete ban on poetry in
Epicureanism very unlikely, as opposed to, perhaps, a distinction
between poetry as entertainment and more serious philosophical
content. More positively, both Philodemus and Lucretius display a wide
and deep knowledge of literature. Yet Philodemus did not write poetry
on philosophical topics, so there remains a gap between Philodemus and
Lucretius.



We can now review attempts make sense of these features as a whole,
namely Lucretius' anachronistic reliance on Epicurus alone, the
absence of inter-school polemics, and the possible clash with his
own' school's views on poetry. To account for these, a
range of motivations have been suggested. Perhaps the least generous
view is that, operating mainly as a poet, Lucretius found in
Epicureanism, or rather its foundational texts, an engaging subject
for poetry (Volk 2002). More generously, we can imagine that even if
Lucretius was a committed Epicurean, he may have been isolated from
the philosophical mainstream and not fully conversant with the most
up-to-date version of his denomination, and even something of a
fundamentalist, seeing no need to go beyond the master's words
(Sedley 1998 ch. 3). More generously still, the narrowing of focus we
find in the *DRN* could have been a deliberate simplification
for the sake of a more appealing introductory work. The mix of
philosophical argument, rhetoric and poetic imagery found in the
*DRN* is typical of protreptic literature, which must avail
itself of imagery and rhetorical persuasion to render the hearer more
receptive to its philosophical arguments (De Lacy 1948; on emotional
appeal, O'Keefe 2021; on rhetoric Markovic 2008). Poetry,
moreover, is the best medium in which to express the intense emotional
impact of such conversion, in this instance the 'heavenly
delight... and awe' (3.28-9 *divina*
*voluptas... atque horror*) Lucretius felt at
Epicurus' revelation of the true nature of the universe. One of
Lucretius' favorite images, used no less than four times in the
*DRN*, is that of illumination: our fear of the unknown, before
Epicurus illuminated it, makes us like children afraid of the
dark.



On any reading of Lucretius' motivations, it will be helpful in
to keep in mind some simplifications that he has made in the material.
First, the single divine savior Epicurus replaces the plural authority
of 'the men' and their different works. Second, technical
language is largely avoided. Third, Lucretius focuses mainly on
introductory exposition and uses a starker set of contrasts between
error and truth, darkness and illumination, before and after Epicurus.
That is at the expense of more extensive or complex technical content,
of dealing with developments in contemporary science or of scoring
points in inter-school polemics. Two positive features, however, are
not lost in the translation to Latin verse. First, Lucretius retains a
strong commitment to clarity and careful organization
(*stoicheiosis*) of the system, with explicit statements of
points needing proof, supporting arguments, transitions between
points, and a general care not to rely upon points not yet proven.
Second is an appeal to empirical data and careful use of analogies to
construct theories. Among these Lucretius will often seek out examples
familiar to his own Roman audience, an effective way of carrying
points.


## 5. Natural science



Epicurus advanced atomist explanations to an unsurpassed degree, yet
Epicurean science remained subordinate to the ethical aim of freeing
us from anxiety in the quest for peace of mind (*Key doctrines*
10-13, *Letter to Herodotus* 37 and 81, *Letter
to* *Pythocles* 85). In Lucretius, this ethical goal is
often left implicit, with ethical material concentrated in the proems
(see section 6). Officially, Lucretius proposes two programs for the
work as a whole. The first curriculum (1.50-61) announces the
poem's subject as 'the high system of heaven and the
gods' and the *primordia rerum*, 'first-beginnings
of things', in other words, a cosmology, including gods as part
of the world, the whole underwritten by a set of first principles.
This is a fairly standard ancient scientific program. But Lucretius
immediately follows that up with the claim that it is not science, but
religion, specifically the human fear of divine governance, that
oppresses mankind and ruins happiness. We are then told, in a second
curriculum (1.127-35), that the nature of soul must be joined to
the previous topics, to dispel such fear. The two together cover the
full Epicurean project, although Lucretius does not formally
subordinate the first to the second.


### Book 1



Book 1 introduces the foundational principles of the system, atoms and
void.


#### 1.147-482: Causation, method, and metaphysics.



Lucretius starts from the observed regularities of nature to argue
that nothing comes from nothing and nothing is reduced to nothing
(147-264). We then get a first methodological point that even
invisible bodies can have observable effects. Lucretius supports the
claim by reference to air and wind and illustrates it through an epic
simile offering an analogy between a windstorm and a mountain river in
flood and extends the point by noting the inability of the individual
senses to perceive the other senses' 'proper
sensibles' (265-328). Lucretius next makes the case for
void as necessary for motion, or rather that motion is inconceivable
without void, and rebuts some counter examples (329-417).
Following that, 'the all', that is the universe, is
asserted to consist of body and void; these two are the only *per
se* entities, no third *per se* thing being conceivable.
All other things therefore are dependent on these and inherit their
properties. Lucretius distinguishes properties that are inseparable
(*coniuncta*, Greek
sumbebekota)
from others that are accidental (*eventa*,
sumptomata). Even time
or facts about the past, like the Trojan war, do not have a
stand-alone existence but are dependent on our world and will not
survive it.


#### 1.483-634: Atoms and their minimal parts



The case for atoms follows (483-615). All perceptible bodies
must be compounds of body and void, but since destruction into nothing
is impossible, there must be a limit to destruction, 'pure
void' and 'voidless body'. Compound bodies must be
made of minute, indestructible bodies, stress-tested over infinite
time. Lucretius does not use the Greek word *atomos*,
'uncut(able)', though Cicero had tried
*individuum*, preferring terms that denote their
generative capacities, such *primordia* ,'first
things', or *corpora prima*, 'first bodies'.
Epicurean atoms are not physically divisible, but they are
theoretically analyzable into multiples of minimal or
'partless' parts (615-34). A minimum unit must
be conceded to account for differences in size and shapes of atoms.
There must also be differences among atoms themselves, for if atoms
could be reduced to a standard minimum unit, no variety in generation
would be possible. In Lucretius, however, the discussion of minimal
parts is much abridged (see also 2.478-580; on atoms, Konstan
2020; on minima, Verde 2013).


#### 1.635-920: Rival theories of matter refuted



From the positive case for atomism, Lucretius veers to a critique of
three rival theories of matter. Three Presocratic philosophers
are put forward as representatives of these theories. First comes
Heraclitus (635-711), leader of the monists, advocate of the
single element fire, with generation operating by rarefaction and
condensation. Empedocles is the champion of the four-element theorists
(712-829) and he generates all things by union and dissolution,
and finally Anaxagoras, advocate of an indefinite pluralism, who
posits an indefinite number of '*homoeomerous*' or
'like-parted' stuffs (830-920) which merely vary in
local concentration. The section may have been imported from
elsewhere. One can suspect an Epicurean and/or doxographic source
at work, whether Epicurus himself (Sedley 1998) or a later one
(Montarese 2012). The key point that Lucretius stresses is that only
atomism can accommodate change while keeping the first principles, the
atoms themselves, completely invariant.


#### 1.951-1118 Infinite universe and space; critique of geocentrism



Following the simile of the honey and the wormwood (921-50),
book 1 concludes with a dizzying transition from microcosm to infinite
universe (951-1051). Lucretius argues that void or space cannot
be bounded: there is always further to go in all directions. And if
so, then body, as well as space, must be infinite, for without
infinite body, creation would run out of matter. (Lucretius here is
relying upon the Epicurean doctrine that up and down are
universal, as he will explain in book 2.) The infinite universe was a
legacy from earlier atomists and had been subject to criticism from
Plato and Aristotle, who argued that the world was finite and unique,
with earth at the center. This is why Lucretius adds a critique of
geocentric cosmology to his positive case for the infinite universe
(1052-1113). 


### Book 2



Book 2 covers atomic motion, atomic shapes, and the emergent
properties of compounds


#### 2.62-332: Atomic motion and the swerve (for this section, see Fowler 2002).



Lucretius resumes his exposition with atomic motion, offering the
famous scientific image of motes of dust in a sunbeam (*simulacrum
et imago* 'likeness and image' 112) to illustrate
ceaseless atomic motion, within or outside of compounds. Atoms travel
at a constant but unimaginably high speed, meeting no resistance in
the pure void. They are much faster even than particles of light
--fire being a compound-- whose constitutive atoms pull and
push one another, causing the particles to have a lower aggregate
velocity (150-64). Atomic rebounds merely redirect them, without
loss of speed. There is a universal up and down, however, and the
weight of atoms will lead them to fall through space, at uniform
atomic speed.



It is at this point that Lucretius introduces the doctrine of the
atomic swerve or *clinamen*, a minimal deviation by atoms from
their straight course that occurs randomly, at no specific time or
place (216-93). The swerve, attributed to Epicurus in our
sources but not attested in our surviving works, is brought in to
answer a narrow hypothetical problem: what would happen if atoms were
all traveling downwards, like drops of rain? Since they travel at
equal speed, they could never overtake each other, nor could they
shift from their straight downward trajectory and collide, so that no
atomic compounds could ever get going. Lucretius maintains that a
minimal deviation -best imagined as a
one-minimum lane-shift on a highway, rather than a change in
direction, an offramp- must take place in order to ensure that
collisions (and eventually worlds?) can arise. The account as we have
it (216-50) is already too brief. But now, quite surprisingly,
Lucretius links it to a second factor, voluntary action
(251-93). Taking voluntary action as a self-evident fact, he
asserts that it stands as second independent reason requiring a
minimal swerve, lest volition be trapped within an infinite causal
chain. The exact meaning of this section has been much debated.
Indeterminism in ancient atomist theory cannot help but remind us of
indeterminism in modern quantum physics, which has sometimes been
invoked to support psychological indeterminism, thereby inviting us to
do the same for Lucretius. Yet the apparent lack of recourse to the
swerve in some substantial surviving sections of *On nature*
book 25, where Epicurus argues for human agency over causal
determinism, leaves it unclear how widely Epicurus relied on the
swerve. Some think a swerve is involved in every voluntary animal
action; a more minimal view requires only that the swerve grant minds,
those most subtle of physical bodies, enough slack from the chain of
causation, over time, to develop an independent domain of agency
(survey in Englert, 2020; on Epicurus against determinism, Kamtekar
2021).



Lucretius returns to atomic motion to assert the permanence of matter
and motion (308-332). Atomic motion does not cease in bodies at
apparent rest, but in cosmic settings the atoms settle into regular
patterns, presumably within compounds, producing regular properties.
To support this Lucretius uses the analogy of distant views: just as
sheep pasturing on a hill are reduced, at a distance, to white dots on
a green background; similarly, the clamor and flashing armor of a
legion being drilled dies down, from a nearby mountain top, to a mere
gleam on the plain.


#### 2.333-729 Atomic shapes and their combinations.



There is a great variety of atomic shapes, with many small variations
(333-477). Like animals, atoms can be classed into types or
species without also requiring that all individuals of the species be
completely identical. These atomic types underlie the diversity, but
also the finite regularity, of phenomenal properties and sensations.
From line 380 and following Lucretius offers examples of the
contrasting properties of various materials, but his inferences from
these perceptible properties to their microstructures is problematic
if referred directly to atoms (Bailey 1947 vol. II p. 866) instead of
to compounds or 'molecules'. The number of atomic
types or shapes, we next learn, is unimaginably large, but not
infinite, since the atoms are finite multiples of finite
*minima* and all atoms are imperceptibly small; but there is no
limit to the number of atoms of each exact shape (478-580).



A fuller account of compounds is then promised by the announcement
that nothing perceptible consists of only one type of atom
(581-88). Instead, however, Lucretius offers an allegorical
image of 'mother earth', the great repository of all
stuffs, rendered through the image of the Asiatic goddess Cybele, the
*Magna Mater* (2.598-660). From the surviving final
sections of *On nature* 14, where Epicurus criticizes Plato in
the *Timaeus* for reducing fire to a single pyramidal atomic
shape, it does seem that Epicurus recognized the four elements as
(the most?) basic types of atomic compounds (Wigodsky 2007). Lucretius
does not delve into this, however, and stresses instead the complexity
of visible bodies. Such variety and complexity do not threaten
the regularities of nature, since they all proceed from finite and
fixed atomic shapes.


#### 2.730-1022 Properties of atoms and emergent properties of compounds



The next section completes the introduction of atoms by distinguishing
between atoms, whose only inseparable properties are shape, size and
weight, and the emergent properties of compounds. Atoms lack
color (730-841), heat, moisture or smell (842-64). As for
sensation, it is also an emergent property of living things, and atoms
do not have it (865-900). This somewhat alienating thought is
then capped with the grand and slightly less alienating poetic idea of
the cycle of life (991-1022, a recap of 2.569-80). We are
all children of heaven and earth, since we grow from the elements and
die back into them; within our world, the emergence and then
disappearance of life are in constant balance, secured by the
indestructibility of the atoms.


#### 2.1023-1174 Infinite Worlds.



As did book 1, book 2 ends with the infinite universe. This time the
infinite universe is the basis for arguing that there are other worlds
than ours; since space is infinite, we cannot be unique
(1048-89). Worlds occur by chance, when the sufficient material
conditions are met, without any need for gods (1090-1104). The
growth and decay of worlds is not a metaphor, but closer to a
biological fact. Lucretius ends book 2 on the pessimistic note that
our world is already in decay (1105-74; but contrast
5.325-37 where it is said to be young).


### Book 3



Book 3 is on the nature and mortality of soul, concluding with the
fear of death.


#### 3.94-416: *the nature and structure of soul*



The soul is a body and not a *harmony* of parts in tension; it
is a biological part of the body, like an organ, which remains active
when the body is at rest, but it is unable to survive separation from
it (94-135). Lucretius distinguishes two main parts of soul
(136-76). The *animus*, roughly mind, is the controlling
part and center of consciousness, located in the chest, the
*anima* more like the nervous system, spread throughout the
body (on partition, Verde, 2020; broader background in von Staden
2000). Both parts are bodily since they act and are acted upon. A more
detailed elemental analysis of the soul follows (177-322): the
*animu*s is made of fine and mobile particles. It is a
composite of breath, heat, air plus a fourth finest and nameless
stuff. The nameless stuff initiates movement, which imparts it to
breath, heat and air; these then move the body. They form a single
body or mixture, but with small variations among individuals. These
elemental-humoral 'idiosyncrasies' run from excess fire (=
prone to anger) to excess air (= too placid). Although these
imperfections cannot be eradicated, they can be controlled with
training. Mind and body cannot survive apart, but each will eventually
be dissolved into their constituent atoms (323-416).


#### 3.417-829: Thirty proofs of the mortality of soul



Lucretius offers an epic catalogue of thirty arguments for the
mortality of soul, mostly turning upon the interdependency of soul and
body for life. Lines 425-669 argue against post-mortem survival,
670-783 against pre-existence, while 784-829 return to
more general considerations. These proofs seek to undermine older
traditional beliefs in the afterlife and underworld (Hades) or attack
Platonic reincarnation and the immortality of the soul. The final
section of the book shifts from the fact of death as the end of all
sensation, to argue that death is not to be feared (see section
6).


### Book 4



Book 4 explains the activities of soul: perception, thought, dreams,
and emotions


#### 4.26-215: the existence and nature of the *simulacra*



*Simulacra* (Greek *eidola*) are thin atomic films that
are constantly emitted in all directions from all larger aggregates,
preserving the structure or shape of the original object
(26-109). They are extremely fine, form spontaneously and
swiftly, and travel at great speed.


#### 4.216-822: sensation and thought.



Sight and related phenomena are treated first (216-378). Vision
is due to the multiple impacts of a stream of
*simulacra*, while other sensations are due to other
kinds of effluences or direct contact. Lucretius examines a number of
visual puzzles to show that the eyes are never wrong, rather the mind
generates false inferences. This leads to an Epicurean critique of
skepticism and a defense of the infallibility of the senses
(469-521). Lucretius replies to the sceptic that reason cannot
refute the senses and any attempt to deny knowledge through the senses
is self-defeating, the very concept of true and false being anchored
in sense-experience. (522-721). The working of the other senses is
discussed before turning to thought (722-822). Mental visions
and dreams are a sort of attenuated inner vision reliant on the impact
of even finer *simulacra* directly onto the soul. These
simulacra are so abundant, at all times, that the mind can focus on
any of them; even fantastical imaginings are real enough, since the
images, like clouds, are constantly forming and coalescing into all
manner of shapes.


#### 4.823-1057: Functions of the body and soul



Lucretius deals with a number of bodily functions, from nutrition to
voluntary motion, sleep and dreams, before transitioning to a more
general critique of erotic love (1058-1287). The transition is
handled by a pointed refutation of teleology aimed at the notion of
body parts as designed to serve a purpose (823-57). In all
cases, Lucretius replies, their existence preceded their use. Unlike
artefacts, which serve a purpose that already exists, for example,
cups for drinking or beds for sleeping, sight was not designed before
there were eyes to see.


### Book 5



Book 5 contains a cosmology, describes the origins of life and the
history of civilization.


#### 5.91-770: Our world



Our world had a beginning and will have an end (91-109). Before
expanding on each of these, Lucretius offers a refutation of
creationist accounts (110-234). The gods do not dwell in the
world, nor did they make the world for man. Even supposing they did,
awkward questions can be raised. What were the gods up to before they
built the world for us? Where did they get the scientific knowledge
needed to plan life? And so on. At 195-234, Lucretius rejects
the idea that the world was designed for human use. In fact, the world
is barely able to sustain us. Most of it cannot support agriculture
and agriculture itself is hard work, with crops sometimes failing. Why
are there so many beasts and pests? They seem to thrive even without
help, while humans are completely helpless when born. Next the
mortality of the world is inferred from the mortality of its component
parts, the four elements, each of which is destructible
(235-415). Against the upholders of an eternal world, Lucretius
asks: why does human history not reach further back than the Theban
and Trojan wars?



Our world did not arise through intelligence or design, but because,
in the infinite universe, as atoms work out randomly all possible
combinations, at some point an accumulation of atoms of a suitable
kind to form our world occurred (416-508). The formation of the
earth is followed with an account of the heavens (509-771). In
his account of the nature and movements of the sun, moon and stars,
Lucretius has recourse to the Epicurean mode of 'multiple
explanations', to be used for phenomena where we cannot
determine, among a number of possible explanations -and
excluding divine causation- which one applies. In such cases we
should stay open to all of them. Of each we can be confident that,
even if not the case in our world, it will be true in some other world
(526-33 and also 6.703-11; on the background,
Epicurus' *Letter to Pythocles* and Hankinson 2013).


#### 5.772-1457: Life on earth, early man, history of civilization



Lucretius returns to the early earth and the origins of life
(772-925). The account, marked throughout by the conspicuous
absence of gods or teleology, is one of the most detailed and
influential in the ancient anti-creationist tradition. First, grasses
and plants sprouted from the earth, who, as mother of all, produced
animals from wombs inside the earth and quasi-milk for those first
animals. That fertility was of brief duration, however. The key
analogy is the earth as a female animal. A limited amount of
still-occurring spontaneous generation, small insects from mud,
underwrites the legitimacy of the comparison, while the notion of a
limited period of fertility explains why large creatures were once
produced but are no more (795-836). Lucretius allows for many
early defective creatures and semi-Darwinian false starts that died
off because they were not viable, could not reproduce, or find
advantageous arrangements, as in domestic animals (878-925).
Although much of this non-teleological account owes an obvious debt to
Empedocles' zoogony, with its phase of random, monstrous
cross-species combinations of limbs (Diels-Kranz B 57-61), Lucretius
corrects the earlier theory by arguing against even temporary
crossings of the species boundary (Schrijvers 1999, Campbell
2003).



Early man was solitary, not social, and much sturdier
(926-1010). Lucretius outlines the hardships of life before
agriculture, fire, clothing, society or law or marriage, but balances
that with the absence of the many ills civilization has brought, such
as warfare or the perils of navigation. This same balance runs through
the history of civilization that closes the book (1011-1457). As
is now widely recognized, Lucretius is not a progressivist, nor does
he see humanity as fallen from a past Golden Age of innocent happiness
and self-sufficiency. At each technological advance he points out the
drawbacks of the new stage. The advances are prompted by nature,
without divine inventors, as mankind recognizes the usefulness of
shelter, clothes, fire, marriage, friendship and family life, the last
of which is framed in Epicurean ethical terms, justice as a social
contract (1011-1027). The origins of language are not due to a
primeval name-giver, but an innate human impulse to make sounds and
the posterior recognition of the utility of designating objects
through sounds (1028-90). A similar story goes for fire and
cooking (1091-1104), the foundation of cities and the rise of
kings and property (1105-35), later replaced by laws and the
fear of punishment (1136-60). After outlining the origins of
belief in the gods (1161-1240; see section 6), Lucretius
continues with the arts of war, metals, weapons (including a weird
account of unsuccessful experiment of bulls, boars and lions trained
for war), clothing, agriculture, music, and simple rustic pleasures,
leading to the final improvements in war and the arts. These accounts
are mere reconstructions, since these origins are mostly unavailable
to investigation, but even without offering multiple alternatives,
Lucretius must think it sufficient to provide for each discovery a
plausible, non-divine origin.


### Book 6



Book 6 explains meteorological and terrestrial phenomena



In keeping with the two-book pattern, book 6 describes the world in
action, doing so by tackling successive meteorological and earthly
phenomena often viewed in popular belief as divine manifestations. The
multiple explanations featured in this section can be matched from
doxographic sources, but the pattern of the book is shaped by
Lucretius. In each case there is an emphasis on destruction or the
threatening aspects of nature, building to the final account of the
Athenian plague, all in responsion to Book 1's theme of birth
and generation (Jope 1989). Lucretius reviews thunder and lightning
(96-422), waterspouts (451-534) clouds and rain, before
passing to terrestrial level with earthquakes (533-607), mount
Aetna and volcanoes (639-711), the pestilential fumes of lake
Avernus (738-839) and other strange springs and fountains. An
extensive account of magnetism -a special challenge for
atomism- comes next (6.906-1089), and then various
pestilences (1090-1137), followed by the gruesome case study of
the Athenian plague. Throughout Lucretius encourages an attitude of
demythologizing detachment before the uncanny or invisible, thanks to
the denial of divine causation and recognition of the 'finite
capacity', *finita* *potestas*, of all natural
processes (6.64-5, cf. 1.76).]


## 6. Ethics



The *DRN*'s opening, perhaps channeling Empedocles,
proposes religion, or rather wrong religion, as the obstacle to human
happiness, for which the cure is physics. Yet as the work progresses
Lucretius provides a richer picture of Epicurean ethics, including
Epicurean hedonism, and outlines a wider range of obstacles to human
happiness. Lucretius does not give a full presentation of Epicurean
ethics, though the end of Book 3 on death comes close, but the proems
offer brief sermons or strenuous pleas for Epicurean values mixed with
pointed diagnoses of contemporary malaises. Thanks to these, by the
end of the 6 books, Lucretius manages a reasonably full picture of
Epicurean ethics and its goal of peace of mind, the capacity to
'face all things with a calm mind' *placata*
*posse omnia mente tueri* (5.1203).



The proem of book 1 opens with a hymn to Venus as world-governing
deity (1.21) and a prayer for her to intervene with Mars, god of war
(1.29-44), both of which are problematic for Epicurean theology
(see section 7). But the hymn also celebrates the generative and
attractive side of nature, Venus as 'pleasure of gods and
men' *hominum* *divomque voluptas* (1.1). The
proem of Book 2 (1-61) also opens with pleasure
(*iucunda* *voluptas* 2.4), but a more refined
psychological pleasure, that of knowing you have escaped ills and are
above the fray in the 'lofty sanctuaries of the wise'
(2.7). Lucretius follows this with the normative claim that nature
calls for nothing else than freedom from pain and a mind at
peace. Other apparent goods such as luxury, social status or glory do
not profit the body or the mind. None of these, moreover, can dispatch
the fear of death; only reason or philosophy can do that. The opening
of book 3 concentrates upon the praise of Epicurus, whose teachings
dispel all fear, so that in contemplating nature, as revealed by him,
we seem to leave the world behind us, to experience divine pleasure
and awe *divina* *voluptas... atque horror*
(3.1-30).



The conclusion of book 3 (830-1094), following the demonstration
of the mortality of body and soul, seeks to remove the fear of death.
Death according to Epicurus is the end of all sensation, it is
*'nothing to us*' (830). To fear being dead
-as opposed to dying- is to suffer from a conceptual
muddle. The hard fact is that *you* will not be at your own
burial, nor will *you* be nibbled by worms in the ground or
suffer torments or rewards in the afterlife, because *you* will
no longer exist. In what has become known as the symmetry argument
(Warren 2004), Lucretius argues that, just as we calmly accept our
non-existence before life, we should view the time after it with the
same indifference. This therapeutic mix of emotion and argument is
only one of many in the close of book 3, which combines philosophical
argument with rhetorical and poetic techniques to great effect.



Not as magnificent, but more appropriately comic is the attack on
erotic love concluding book 4 (1058-1287). Lucretius demotes
cosmic Venus from the proem of 1 to human sexual desire and dismisses
erotic passion as simply an excessive form of a natural desire.
Lucretius' attitude seems less philosophical than middle-aged or
medical, with emphasis on practical sexual education. We are informed
that women also have a libido, what positions are best for conception,
and that devotion and clean habits are the basis of stable
attachment.



The proems of 5 and 6 concentrate more directly on Epicurus. The proem
of 6 (1-95, especially 10-33) contains the most explicit
summary of Epicurus's moral benefactions in the poem. Building
on the account of civilisation from book 5, it places Epicurus in
historical Athens, and explains how, despite having every material
need satisfied, the Athenians were still unable to achieve peace of
mind. For this they needed Epicurus to teach them the limits of fear
and pleasure and a scientific understanding of the world (31-2).
The function of the last, as Lucretius expands in managing the
transition to the meteorological subject of the book, was to banish
fear of the divine (50-67), which was particularly linked to the
heavens in the imagination and liable to insinuate itself into our
thinking through ignorance of the workings of nature (see section
7).



The gruesome depiction of the Athenian plague concludes the poem
(6.1138-1286). As noted, its focus on death and suffering
corresponds to the poem's opening scene with Venus and birth.
Epicurus taught that suffering could be resisted through mental
focusing on the joys one had already experienced, while extreme pain
could be endured through the knowledge that it would be short-lived
(*Key doctrines* 3 and 4). Though moderns tend to find this
less than convincing, Epicurus put it into to practice for the benefit
of his disciples in recording how he coped successfully with the
painful circumstances of his own death (*Diogenes Laertius*
10.22). In the later summing-up formula of Epicurean ethics, such
cheerful endurance was the final ingredient in the 'fourfold
remedy' for happiness: 'God holds no fear, death no
worries; the good is easy to get; evil easily endured'
(Philodemus, *Against the Those who Claim to be Readers*,
*PHerc* 1005, 4.9-14). Although Lucretius dwells on the
helpless mental anguish of the Athenian plague victims, he does not
offer an explicit Epicurean remedy. Some hold that the ending we have,
which merely depicts the ailment and not the cure, is the one
Lucretius intended because, thanks to all we have learnt, we can
supply it ourselves. For others, the ending still awaits its final
revision, because it is hard to imagine that Lucretius, having dealt
with the first three explicitly in the poem, would have left the
fourth merely implicit.


## 7. Religion



Lucretius opens the *DRN* with a traditional prayer to
anthropomorphic Venus, as a world-governing deity (1.21), to support
his poetic project and to pacify her lover Mars (1.21-40). This
is already problematic, but the opening sequence is made even more
puzzling by the immediate sequel, a clear statement of the most
important Epicurean departure from popular belief about the gods, the
denial that they intervene in the world, because that is incompatible
with their eternal happiness, 1.44-9:



> 
> For the nature of divinity must necessarily enjoy immortal life along
> with the greatest peace, far removed and separated from our affairs;
> for without any pain, without any danger, itself mighty by its own
> resources, needing us in nothing, it is neither moved by benefactions
> nor touched by anger. (transl. Rouse-Smith with modifications)
> 



The passage is fully orthodox (*Key doctrines* 1, *Letter to
Menoceus* 123) and the same lines recur later at 2.644-51,
after the *Magna Mater* passage, where they make much better
sense as a correction, from an Epicurean standpoint, of the preceding
allegorical treatment of the earth as mother of the gods. But the
brutally abrupt way the lines undercut the prayer to Venus is
difficult. Many editors have suggested that 1.44-9 are an
intrusion and should be removed or at most reflect an incomplete draft
(defense in Bailey 1947 vol. II pp. 601-4; survey in Butterfield
2020). But regardless of whether we keep or reject 1.44-9, it
seems likely that Lucretius meant us, later on and from hindsight, to
reinterpret the opening scene in some way more compatible with
Epicureanism.



Lucretius next describes the intellectual hero, whose 'flight of
the mind' liberated humanity through science (61-79;
Epicurus, again in hindsight, though not named), followed by the
example of human sacrifice of Iphigeneia (80-101), to condemn
wrong religion. (The example is quite literary: human sacrifice
was not a feature of Roman religion.) The main focus thereafter is
natural science, the atomic world free from divine governance, and
Lucretius does not return to the gods themselves until book 5. At
5.146-55 we learn that the gods have exceedingly fine bodies, so
that they cannot be seen or touched, only grasped by the mind (that
is, via especially fine *simulacra*, see below). Accordingly,
they do not dwell in the world. Lucretius' promise to tell us
where they dwell (5.155) is never fulfilled, but other Epicurean
sources hold that the gods dwell in the inter-cosmic voids. In
Lucretius this much seems strongly implied by the imagery used at
3.14-30, when the world falls away as we experience
*divine* pleasure.



The origins of human belief in gods are given later in book 5 as part
of the history of civilisation (1161-1240). Early men, both with
waking mind and in their dreams, had visions of the gods as beings of
great beauty, stature and strength. As these figures did not seem to
age, they attributed to them eternal life (1169-82). It was then
that, unable to puzzle out the workings of the heaven, they
'took shelter' by, as it were, handing over the governance
of the world to these gods. That, for Lucretius, was the great fall.
At 1204-1240 Lucretius offers some impressive lines on
nature's capacity, still now, to cow and grind down humanity, as
when we contemplate the majesty of the heavens or are shaken up by the
thunder and lightning of a powerful storm.



Lucretius' fullest positive account of the Epicurean gods and of
human piety is given in the proem of book 6 at 68-78:



> 
> Unless you spew all these errors out of your mind, and put far from
> you thoughts unworthy of the gods and alien to their peace, their holy
> divinity, impaired by you, will often do you harm, not that the
> supreme power of the gods is open to insult, so that it should in
> wrath thirst to inflict sharp vengeance, but because you yourself will
> imagine that they who are quiet in their placid peace, are rolling
> great billows of wrath, you will not be able to approach their shrines
> with placid heart, you will not have the strength to receive with
> tranquil peace of spirit the images (*simulacra*) that are
> carried to men's minds from their holy bodies, declaring what
> the divine shapes are. (transl. Rouse-Smith)
> 



In the *Letter to Menoeceus* 123 Epicurus enjoins us to
'think of a god as an indestructible animal' and
explains that to form a proper conception of the divine, we must
reject all that is incompatible with that core notion (as above
1.44-9). What this book 6 passage adds is an explanation of how
we must make ourselves receptive to the gods, so that their images may
impinge upon our minds. The result is that it is we who are in
large part responsible for shaping our conception of the gods. Peace
of mind, while mostly an Epicurean end in itself, in this case also
becomes instrumental to the formation of a proper conception of the
gods.



Still, there are problems. Since our access to the gods proceeds
exclusively through *simulacra*, and it is all too easy to form
a wrong conception of the gods, one can worry how any certain
conception about them is possible (why no multiple explanations
here?), or why we should think that these gods are anything above and
beyond those *simulacra*, or again if it actually matters that
there should be such beings, since they do not answer prayers or
punish wrongdoing. Add to that the numerous difficulties and awkward
questions that must be overcome to support the extra-cosmic life of
such anthropomorphic gods with quasi-bodies and quasi-blood (see
Cicero *On the nature of the gods* 1.43-9), and one can
see how Epicurus' ancient critics felt free to accuse him of
atheism, the extra-cosmic gods merely providing plausible denial. An
echo of that tension is still heard in the modern scholarly debate
about these gods, confronting realists, who hold that Epicurus really
was committed to the existence of these gods (Konstan 2011) and
idealists, who hold that we are mostly responsible for constructing
our own conception of an ideal life (Long and Sedley 1987 section 23;
Sedley 2011). Perhaps the only relative certainty is that Lucretius,
who above distinguishes the gods from their *simulacra*, is
officially a realist, as is Philodemus (Essler 2011).



Yet however that theoretical debate comes out, it makes little
difference at the practical level, where the exemplarity of the gods
is far more important. By focusing our minds upon the perfect life we
conceive these gods to live, we can find or construct models on how
best to live out our own finite span. Such exemplarity in turn appears
to be the best way to understand the various claims made by the
Epicureans, followed by Lucretius, that Epicurus himself was a
paradoxical 'mortal god' (*deus* *ille fuit*
5.8) who taught his followers how to lead 'a life worthy of the
gods' (3.322) that is, a life lived as far as possible in
imitation of the blessed and imperturbable gods (Erler 2002). The
exemplary life Epicurus led - and often in other Epicurean
literature his immediate disciples as well - could function as a
suitable model for such 'focusings' of the mind.



One last aspect of Lucretius' deification of Epicurus that
appears to go beyond his status as model is his depiction as the
greatest benefactor of humanity in the proem of Book 5. This, however,
may owe more to the popularity of Euhemerism at Rome in the first
century B.C. than anything Epicurean. Euhemerus (active c. 300 BCE)
proposed that the gods of myth had originally been men, who had been
granted immortality in recognition of their discoveries or gifts to
mankind, and whose names recorded their accomplishment, for example
'Bacchus' for wine. This rationalistic work had an
understandable vogue in the Hellenistic period, where divinization of
kings was not infrequent, and had been translated into Latin by
Ennius. Lucretius claims that Epicurus' benefactions surpass the
discoveries of agriculture, wine, and even the heroic deeds of
Heracles, so that he should count as the greatest benefactor of
mankind. Whereas these benefactors only improved mankind materially,
Epicurus purged our hearts from troubles and desires (5.49-51).
The passage is in good part a rhetorical exercise in which Lucretius
shows that he can beat the Euhemerists at their own game, while also
subtly undermining them, since Epicurus hardly strove after
immortality, as shown by the past tense *fuit* (Gale 1994
appendix 1). More obviously the sequence serves the literary function
of introducing the main topic of the last third of the book, the
growth of civilisation. But unlike the discoverers celebrated and
immortalised by Euhemerus, Lucretius' discoverers in
5.1011-1457 are all anonymous.


## 8. Influence and reception



Whether or not Lucretius operated on the margins of the Roman world,
there is no doubt that by the next generation, in poetry at least, his
work became mainstream and his influence extensive (Hardie 2009). In
imperial Latin prose, with the exception of Seneca in his *Natural
Questions*, he is mainly discussed as a
poet. His transformation into a philosophical source for
Epicureanism is first seen in the hostile Lactantius and the more
ambivalent Arnobius (Gatzemeier 2013). In Latin poetry he was read
continuously until the end of antiquity (Hardie 2020); his presence in
late antique Latin prose remains largely unexplored.



The *DRN* reached us through two 9th century
Carolingian manuscripts both now in Leiden, O and Q (on the early
textual history and for discussion of the unusual
'capitula' see Butterfield 2013). Lucretius re-entered
circulation when he was rediscovered in 1417 by the papal secretary
Poggio Bracciolini (on the story of that discovery, Greenblatt 2011).
Later in the same generation the migration of Diogenes Laertius'
*Lives of the Philosophers* to Italy, followed by its
translation into Latin and various first printings, allowed Epicurean
ideas to be studied first-hand and eventually play a leading but
hardly exclusive role in the scientific revolution and the rise of
early modern moral thought, especially social contract theories (on
Renaissance dissemination, Palmer 2014 and 2020; on the influence of
ideas, Wilson 2008). Lucretius' early modern reception is now a
flourishing scholarly enterprise and most recent collections of essays
on Lucretius have a substantial section devoted to this aspect (for a
start, see Gillespie and Hardie 2007 and Mitsis 2020). Though
Epicurean ideas were suspect, and an easy label for accusations of
atheism and crude hedonism, the *DRN* was never put on the
Index of banned books, so long as it was kept among the learned. But
early translations into vernacular languages were banned (Prosperi
2020). Many of Lucretius' most open humanist critics were also
his best students and editors. Denys Lambin's watershed 1563
edition and commentary praises Lucretius as the 'sweetest'
of all Roman poets but points out the 'correct'
Aristotelian answer for every Lucretian-Epicurean departure. Montaigne
studied Lucretius intently and used the *DRN* as a regular
quarry for arguments, see for example the presence of book 3 in his
essay 'Que philosopher, c'est apprendre a mourir.'
Pierre Gassendi's Christianity-compatible atomism, built up out
of Lucretius and Book 10 of Diogenes Laertius, did more to
re-establish empiricism and attack Aristotelianism than produce much
in the way of atomism-based science, although it did open up
theoretical space for later scientists, in Britain more so than in
France (Jones 1989).