Sentire et Sperare:
The Use of Imagery in the De Rerum Natura

by Katie Smith

In Sophocles' drama, Oedipus Rex, Oedipus the King experiences a series of horrifying revelations which bring him face to face with the truth of his incest, causing him to gouge out his eyes in shame. This act is a reaction to a mistake he commits while he is unaware of his crime -- a mistake he realizes is now irreparable. This scene gathers a deeper symbolism in light of Epicurean thought; in the De Rerum Natura, Lucretius subtly impresses in his descriptive imagery and analysis of physics that the senses, particularly the sense of sight, are to the Epicurean mind the sole source of truth.

Lucretius employs imagery to present many of his ideas to the reader. In the proem of book four, he depicts a doctor giving children a bitter, curing wormwood in a honey-rimmed cup; Lucretius suggests that he will do the same to the reader with his philosophy.[1] Thus, his reader is to perceive this philosophy with senses of taste, sight, touch, and even smell. A few lines later, Lucretius implies that he will explain his philosophy until his reader becomes fully aware of its significance: tibi forte animum tali ratione tenere
versibus in nostris possem, dum percipis omnem
naturam rerum ac persentis utilitatem.[2]

[I have done so in the hope I might in this way be able to hold
your attention in our verses, until you perceive the whole
nature of things, and are fully aware of its usefulness.[3]

Lucretius uses the verb persentio, a reinforcing compound form of sentio, “to sense.” His goal is to incorporate all of the senses with his words, in order that the reader might “take in” the entire nature of the world as Lucretius understands it.[4] It is not enough merely to read his philosophy; rather, one must fully experience it, as persentio implies.

Lucretius also uses imagery to provide the reader with insight into the physical nature of things. During his discourse on the nature of images, Lucretius explains that visible images are extremely fine particles emanating from material bodies and striking the eye.[5] He gives the example of the reflection of stars in a pond, and then inquires,

Iamne vides igitur quam puncto tempore imago
aetheris ex oris in terrarum accidat oras?
Quare etiam atque etiam mitti fateare necessest
corpora quae feriant oculos visumque lacessant.[6]

[Don't you see how in an instant of time an image
falls from the shores of heaven to the shores of earth?
Wherefore again and again it must be admitted that with wondrous
bodies which strike the eyes and stir up sight.]

He asks his reader, it seems, both to understand and to see, with the help of the numerous images he presents as metaphors, the way in which light physically travels and the way in which the eyes receive it. In this case he is marveling at the speed of light. These lines, however, introduce a long discussion of sensory perception and the ability to distinguish (internoscere) facts, which in turn more clearly defines his epistemological stance.[7] He mentions that humans are able to discern the place or at least the direction from which an image, breeze, smell, or voice comes. In these lines, he explains that humans, by deduction, can even perceive how light, sound, and other sensed things travel.[8] After describing the nature of optical illusions, he concludes with the formulaic statement that one knows nothing without the senses:

Denique nihil sciri si quis putat, id quoque nescit
An sciri possit, quoniam nihil scire fatetur....
...invenies primis ab sensibus esse creatam
notitiem veri, neque sensus posse refelli.[9]

[Next, if anyone thinks that nothing is known, he also doesn't
know whether this can be known, since he admits he knows nothing....
You will find that the concept of truth is created first of all
from the senses, and that the senses cannot be refuted.]

Lucretius believes that we, as humans, have no solid case for truth except that which is given through the senses.

One of the most frequent uses of imagery is to assist in the proof of the existence of primordia, or first beginnings. One of his most celebrated illustrations is that of sheep on a hillside:

Nam saepe in colli tondentes pabula laeta
Lanigerae reptant pecudes, quo quamque vocantes
Invitant herbae gemmantes rore recenti,
Et satiati agni ludunt blandeque coruscant;
Omnia quae nobis longe confusa videntur
Et velut in viridi candor consistere colli.[10]

[For often on a hillside, cropping in their glad pastures,
wool-bearing flocks creep on wherever the grass, sparkling
with fresh dew, calls out and invites each of them,
and the lambs, now full, play and gently butt their heads.
All these things appear blurred to us from a distance,
and stand still like a white blotch on a green hillside.]

From far away, sheep give the appearance of white, immobile splotches. As Lucretius points out, there is much more detail to these splotches than can be understood from afar. Depth perception is an important aspect of Epicurean epistemology. To carry on the metaphor, knowledge of something or someone can be understood as superficially as a white splotch on a hillside, or as intricately as bleating, butting sheep. Such is the case with everything one perceives. The initial perception of something is, to Lucretius, only part of the picture; one cannot possibly understand the physical world without a closer look at it.

Robert Wardy comments on the purpose of Lucretius' imagery: “Lucretius must take advantage of imagery and analogy in order almost to bring before our senses the imperceptible atomic character of things.”[11] Wardy explains that this process includes a “perspectival shift” which enables us to see beyond the real images of the world. “Mental vision,” as Wardy calls it, penetrates further than physical vision because it allows us to see the primordia inside our mind. Outside the mind, primordia are invisible. Wardy uses Lucretius' image of a sunbeam to explain this idea.

In Lucretius' understanding, the senses are the definition of our own essence. In book three, after discussing how important senses are for the comprehension of the mind, he presents the reader with this image:

...sic animus per se non quit sine corpore et ipso
esse homine, illius quasi cod vas esse videtur
sive aliud quit vis potius coniunctius ei
fingere, quandoquidem conexu corpus adhaeret.[12]

[The mind itself is unable to exist by itself without body and the person.
The body seems to be, so to speak, the mind's vase, or whatever
other image you wish to invent more closely joined
to it, since the body clings to it with interconnections.]

In this passage, Lucretius clarifies that any one sense will not bring the entirety of truth; rather, each of the senses plays a partial role in the complete comprehension of truth. Vas denotes a vase, vessel, or even utensil.[13] The whole body, to Lucretius, is merely the epistemological utensil for one's own mind. This is a clear illustration of the way in which the cliché “you are what you know” underlies Epicurean philosophy.

The senses are, in De Rerum Natura, not only the gateway to the truth from our own perspective; they also serve as a means of connecting to the being and perspective of another. An example of specific importance to this idea is the image of the cow in search of her missing calf.[14] This image contains a unique parallel. The mother recognizes a specific calf as her own. As she searches “with her eyes” among the many beasts of the field in order that she might recognize her own calf, none of the other calves will replace the presence of the one.[15] The same recognition is true for the calves a few lines later, as they all return to their own ubera lactis, the milky udders of their mothers.[16] Here each can taste its own mother's milk and can be refreshed with the knowledge of her presence. It is also sustained by the life it receives in the milk. By the taste of the milk each recognizes and participates in the being of its own mother.

This metaphor represents the way in which Epicurean epistemology works. Humans recognize and understand the nature of things with their senses: the calves by taste, the cow by sight. The other calves are to the cow merely species, or images, representing that for which she is looking but not contributing to the essence of her own calf.[17] Such is the case, according to Lucretius, with the many sensations humans experience. We use our senses to determine the nature of someone or something else that exists outside of our own person. The senses are our only path to the animus, or spirit, of another. Until the cow sees and touches her own calf, whom she has learned to know by means of her own senses, she will not believe that the calf is beside her.

In the final lines of book four, Lucretius completes a discussion on love and sexual pleasure, having asserted that love is dangerous to the mind because it involves emotion. He explains that the senses, if misused, can actually become a catalyst for love and harmful emotions that block the mind from receiving knowledge properly. He reiterates:

Quod superest, consuetudo concinnat amorem.
Nam leviter quamvis quod crebro tunditur ictu,
vincitur in longo spatio tamen atque labascit.
Nonne vides etiam guttas in saxa cadentis
umoris longo in spatio pertundere saxa?[18]

[What is more, close familiarity brings love into existence.
For however lightly anything is struck by frequent blows,
it is yet overcome in a long period of time and yields.
Don't you also see that drops of liquid falling
on rocks bore through the rock in a long period of time?]

Walter Englert's translation suggests that Lucretius implies “familiarity” with consuetudo, indicating the kind of familiarity that is a result of allowing the emotions to take over one's ratio.[19] This discussion demonstrates how the senses can be mistaken. Lucretius understands that the senses only enlighten our minds if they are used for the purpose of enlightenment. Phillip de Lacy, in discussing the way in which the gods maintain a detached ataraxia, explains Lucretius' belief that man must become a spectator to the world.[20] According to de Lacy, “As spectator, man is not limited to the sphere of immediate experience, but may with Epicurus pass through the flaming walls of the universe and see the whole of reality.”[21] Thus, Epicurean epistemology seems to be an extremely intricate mental process. One must use the senses in an objective manner, as he mentions in the following sentence. Sexual sensation is an active and emotional experience. It is not mentally detached; rather, it is physically attached. In this way it contributes nothing to one's knowledge of physics, another person, or oneself.

In the lines cited above, Lucretius also illustrates the image of water dripping on a rock to demonstrate that the misuse of the senses will affect our ability to gain knowledge. Over a long period of time, the water changes the shape of the rock. In the same way, the misappropriation of the senses to a non-epistemological end will warp one's epistemological abilities.

The final scenes of the De Rerum Natura provide images of desperation due to disease. Lucretius indicates here also that when the senses are disrupted, they can no longer bring enlightenment. The sick in book six have their eyes wide open, as if seeking truth passionately but too late.[22] Lucretius describes, “perturbata animi mens in merore metuque.”[23] These sick people's minds, indeed their very animi, are affected by the fear of death this sickness brings. This scene, as well as many others in book six, represents the sickness of many who do not use their senses properly; the result of this sickness is fear. All of the senses of the victims of disease are mutilated: the spit is yellow, taste becomes foul, limbs tremble with pain, the nose becomes cold.[24] Lucretius explains with this metaphor that the senses are only the source of truth if they are healthy. Fear disrupts the epistemological desire of the sick. The living relatives also are affected by this fear as they bury their dead. Lucretius ends the poem:

Perturbatus enim totus trepidabat, et unus
quisque suum pro re compostum maestus humabat.
Multaque suos consanguineos aliena rogorum
insuper extructa ingenti clamore locabunt
subdebantque faces, multo cum sanguine saepe
rixantes potius quam corpora desererentur.[25]

[For the whole populace was perturbed and in a panic, and each one,
grieving, buried his own dead hastily, as time allowed.
The suddenness of events and poverty led to many horrible actions.
For they placed their own blood-relative with tremendous wailing
on top of funeral pyres heaped high for others
and set torches beneath them, often violently quarreling
with great bloodshed rather than desert the bodies.]

The citizens of Athens tremble as they bury and burn the corpses of their beloved relatives. This trembling affects their rational abilities, for they would rather shed the blood of those unrelated than desert their relatives. Lucretius employs a pun with consanguineos and sanguine (6.1280-1286), demonstrating the ridiculousness of their reasoning.[26] In his commentary on these final lines, Stanley Barney Smith suggests that death has conquered the essence of these people, who think that pietas (piety) is more important than veritas (truth). Rather than observe reality, they react violently to it. In the last line, although it is not directly stated, one receives the image of a desperate man clinging to his dead daughter, mother, or wife, wishing desperately that circumstances were different. By clinging to a lifeless body, he wishes to restore life. To an Epicurean this action is irrational, since the life or identity of a person lies within the mind.

Even to Lucretius, death represents a bitter reality, an unresolved mystery. Ideally, however, it should not affect our quest for truth. Those stricken with plague or caught up in lust are blinded from ataraxia and enlightenment because of their confused senses. Once again, we remember the image of Oedipus, caught up in his own lust and violence and blinded by them. When Oedipus discovers the truth he chooses not to see it; Lucretius, however, encourages us to embrace it, and thus to find hope even in difficult circumstances. Lucretius ends with death in order that his reader, now having imbibed the very essence of ataraxia, may have life and epistemological purpose.


[1] This passage is formulaic and also occurs in 1.926-50.

[2] De Rerum 4.23-25.

[3] All translations taken from Walter Englert, trans., De Rerum Natura.

[4]Gloss of percipio in l.24.

[5] De Rerum 4.145-213.

[6] Ibid. 4.214-17.

[7] Lines 218-253 in book four discuss the effects of various things such as the ocean, the darkness, the wind, and colors upon our various senses. The mixture provides the reader with mental images of the effects of things on each of the five senses.

[8] In 4.214 Lucretius uses an indirect question with quam to indicate that, when light falls from heaven to earth, we do not only see it but also understand the way in which it falls.

[9] De Rerum 4.469-70, 478-9.

[10] Ibid. 2.317-22.

[11] Robert Wardy, “Lucretius on What Atoms Are Not,” 121.

[12] De Rerum 3.554-7.

[13] These glosses are the definitions presented in the Lewis Latin Dictionary.

[14] Lines 348-65 discuss the significance of visual identification.

[15] See 2.357: “omnia convisens oculis loca...” [searching every place with her eyes] and 2. 364-5: “nec vitulorum aliae species per pabula laeta/ derivare queunt animum curaque levare....” [nor are the appearances of other calves in the glad pastures able to divert her mind and ease her care.]

[16] De Rerum 2.370.

[17] Ibid. 2.364.

[18] Ibid. 4.1283-7.

[19] Ratio is most nearly translated “reason.”

[20] Ataraxia can mean “bliss” or “detached peace.”

[21] Phillip DeLacy, “Process and Value: An Epicurean Dilemma,” 117.

[22] De Rerum 6.1180.

[23] Ibid. 6.1184. “perturbata animi mens in merore metuque” [the rational facility of the mind was perturbed by grief and fear].

[24] De Rerum 6.1188-93.

[25] Ibid. 6.1280-1286.

[26] Cosanguineos, “relatives;” sanguine, “blood”


De Lacy, Phillip. “Process and Value: An Epicurean Dilemma.” Transactions and Proceedings of the American Philological Association 88 (1957): 114-126.

Englert, Walter, trans. De Rerum Natura. Newburyport: Focus Philosophical Library, 2003.

Lewis, Charlton. An Elementary Latin Dictionary.Oxford: Oxford University Press, 1997.

Lucretius. De Rerum Natura.Madison: University of Wisconsin Press, 1942.

Smith, Stanley Barney. Commentary. De Rerum Natura. Madison: University of Wisconsin Press, 1942.

Wardy, Robert. “Lucretius on What Atoms Are Not.” Classical Philology 83 (1988): 112-128.