 Hi, I'm Peter Adamson, and you're listening to the History of Philosophy podcast, brought to you with the support of King's College London and the Lieberhulm Trust, online at www.historyoffilosophy.net. Today's episode, Reaping the Harvest, Lucretius. It began in the early afternoon in August. From far away it was visible as a towering cloud of smoke, which resembled an enormous spreading pine tree. Closer observers were almost immediately buried in ash and battered by falling stones, killed almost without warning. That was in the nearest city, Pompeii. A bit further away, in Herculaneum, they had time to evacuate, but they did not run far enough. That night a blast of hot wind tore through their city, killing anyone left in it and many hundreds who had taken shelter along the coast. This was, of course, the explosion of Mount Vesuvius in 79 A.D. Pliny the Younger is our eyewitness. He himself was further away still than Herculaneum, and lived to write letters about the event to the historian Tacitus. In them he describes the darkness falling, not, as he says, the darkness of a moonless night, but utter blackness, as in a shut room where the lights are snuffed out. Ash and fragments of stone fell like rain, as everyone near him panicked, some clinging to the hope that the gods would save them, but most abandoning their faith and despairing in the face of this apocalypse. It would have been no consolation to the victims to learn that there is, for historians of philosophy, a significant silver lining to this particular dark cloud. Like any respectable Roman town, Herculaneum had respectable citizens who lived in respectable villas. In one of these was a library, containing roll upon roll of papyrus. These books were charred into solid blocks and left buried under meters of ash and rock, where they would be discovered almost 2,000 years later. In the 18th century, archaeologists dug out the papyrus rolls and began to peel them apart. Now they can be read with advanced scanners without damaging them physically. The most sensational find among these Herculaneum papyri was a collection of books on Epicureanism. It seems to have been assembled by an Epicurean philosopher named Philodemus. Thanks to Mount Vesuvius, we have the charred remains of many works by Philodemus and, even more excitingly, the otherwise lost work on nature by Epicurus himself. If you'll pardon the pun, this find speaks volumes about the influence of Epicureanism. Of course the texts, fragmentary though they may be after their ordeal, are a rich source of information about Epicurean thought, but their mere presence in an aristocratic library of a Roman town is itself telling. We've already seen that as late as the 2nd century AD the Epicurean enthusiast Diogenes of Oinoanda had letters of Epicurus and other teachings of the school inscribed in stone in modern-day Turkey. Herculaneum shows us that Epicureanism had already made incursions into the upper crust of Roman society by the 1st century BC. This is confirmed by Cicero, who lived in the same century. He was no Epicurean, but he wrote philosophical dialogues, pitting the teachings of various schools against one another. For him, Epicureanism is one of the main traditions, one to be set against the Stoics and skeptics. Indeed, all the main Hellenistic schools managed the transition from Greek to Latin philosophical literature. This is especially true of the Stoics, who, as we'll be seeing in episodes to come, had a kind of rebirth in the world of the Roman Empire. Epicureanism had its greatest flourishing earlier, here in the 1st century BC, around the time that Rome itself made a transition from a republic, controlled by the aristocratic senate, to an empire. This is the age of Caesar, of Cleopatra, and of Cicero himself, no mean player on the political stage. In addition to the extensive information Cicero provides in his dialogues about Epicurean teaching in his day, he also alludes in one letter to a man who we must recognize, with all due respect to Philodemus, as the greatest representative of Epicureanism after Epicurus himself, the poet Lucretius. In 54 BC, Cicero writes in approving terms of Lucretius, and a few decades later, the poet Virgil works a verse of praise for Lucretius into his Georgics, so Lucretius was known to his contemporaries. Sadly, as a historical figure at least, he is barely known to us. We do know that he wrote one of the great works of Latin literature, and one of the greatest attempts to render philosophy into verse. This is De Rerum Natura, On the Nature of Things. It does what its title says. Lucretius expounds the nature of things, from the atomic structure of the universe, to the mechanics of lightning and magnetism, from the fear of death, to sexual ethics. The poem seems to be based closely on Epicurus' work On Nature, as we can see by comparison with the burnt remains of that work found in Herculaneum. But Lucretius did not just write an expanded poetic version of Epicurus' Greek treatise on physics. He wrote an expanded poetic version of this Greek treatise in Latin. Like his contemporary Cicero, Lucretius works directly with Greek texts and attempts to convey ideas from those texts in a new tongue. Both he and Cicero apologize more than once for their inability to render Greek philosophical terms perfectly in Latin. The Epicurean Philodemus and Cicero both made the pilgrimage to Athens, the home of philosophy, and studied with masters there. To be a lover of wisdom in Roman society was, at least in this period, to be a lover of things Greek. In particular, the Greek who Lucretius loves is Epicurus. Of the six books in On the Nature of Things, four start with extravagant praise for Epicurus, who is hemmed quite literally as a god. Never mind that in this very poem, Lucretius says that the gods have nothing to do with us but rather exist far away from us in the infinite void. Lucretius is entirely open about the fact that he is following Epicurus and setting his ideas down in Latin verse. The six books of the poem take us through the high points of the Epicurean theory, including atomism, the centrality of pleasure, and the absurdity of fearing death or the gods. Lucretius says, as I mentioned last time, that his poem aims to present this teaching in a more pleasing way, like smearing honey on the rim of a cupful of medicine before giving it to a child. His avowed aim is to convert the reader to the received wisdom of Epicurus, the reader being in the first instance an aristocrat named Memmius, the addressee of the poem. Does Lucretius bring anything to Epicureanism beyond his ability to put it into difficult but beautiful Latin hexameter verse? He does indeed, and I would insist that the literary achievement is inseparable from the philosophical achievement. Perhaps Lucretius' greatest strength is the ability to conjure powerful and plausible images for Epicurus' ideas. He compares the quick moving atoms of the soul to poppy seeds, the constantly moving atoms within an apparently unmoving body to the mad fracas of a battlefield seen from a distance as an unmoving blur. In one of my favorite passages, he is trying to persuade us that atoms have many, subtly different shapes. To illustrate, he mentions a slaughtered calf, whose mother cow is forlorn in her grief. She is described in loving detail, searching for her lost offspring, scanning the ground for its beloved hoofprints, carrying nothing for other calves, though they all look the same to us humans. In the same way, atoms with different shapes seem interchangeable until we carefully consider the point. As it happens, Lucretius is going to go on to say that every shape of atom occurs an infinite number of times in the universe, which pretty much undercuts his point. But when the point is made with that much style, one hardly cares. Similarly powerful is the end of the poem. Lucretius is trying to explain the causes of disease. He unleashes a terrifying description of the classical plague of Athens, inspired by the historian Thucydides. Here Lucretius seems to want us to see what Pliny says the victims of Mount Vesuvius realized as they thought they would die. The gods do not care about us. We are on our own. Now I know what you're thinking. This is all well and good, but are there any new ideas here? Yes and no. Some ideas absent from the remaining writings of Epicurus do turn up, but it is usually assumed that whatever is unprecedented in Lucretius is taken from the lost parts of Epicurus' writings. A minor example would be the account Lucretius offers for magnetism. Invoking the atomic theory, he suggests that the magnet sends out a powerful stream of particles towards nearby metal. These push aside the air between the magnet and the metal, creating a space dominated by void. But air is pressing on the magnet and metal from all other directions, so they lurch towards each other into the space between them, which provides less resistance. More important would be a distinction he introduces within the Epicurean theory of soul. He draws a contrast between two aspects of soul. With his newfangled Latin, he calls these two aspects animus, sometimes translated mind, and anima, sometimes translated as spirit. The ruling part of the soul is the mind or animus and is seated in the chest, as Aristotle and the Stoics taught. The spirit, or anima, is dispersed through the whole body. You can keep living without parts of your spirit, as we can see from the fact that people survive when limbs are amputated. But your life literally depends on the continued presence of the mind. It is our commanding faculty and initiates our emotions. Still, it should be noted that Lucretius' animus is not really a mind in our sense, or indeed in Aristotle's sense. Lucretius illustrates its powers mostly through examples of emotion, rather than, say, intellectual activity or consciousness. This brings us to a fundamental issue, one already discussed by Epicurus. It is one of the running themes of Hellenistic philosophy as a whole, and will occupy our attention in many episodes to come, because philosophers of all traditions will feel the need to say something about it. Lucretius is one of the first to give the issue a technical name, libera voluntas, meaning free volition or free will. He draws our attention to a fundamental difference between creatures that can exercise free volition and other things like inanimate objects. With his flair for vivid examples, he describes what happens at the start of a horse race. When all the horses are allowed to charge ahead, there is the briefest of moments before they move. We might think instead of the few hundredths of a second between the starting gun and the sprinters leaping out of the blocks. This is unlike, say, one rock hitting another. The rock that gets hit doesn't pause before reacting, it just moves. That is because it is not moving itself, it is being moved by something else. Plato and Aristotle already drew attention to the capacity of animate beings to move themselves, but the Epicureans may have been the first to worry about the conditions under which this was possible. In particular, they worried that if everything in the universe happens as a matter of necessity, the world unfolding inevitably from the past to the present, then nothing would have a power of free volition. And they should worry. After all, their physics describes the world as the result of atomic collisions, each of which seems to be like one rock hitting another. This suggests that the difference between the horse and the rock is only apparent. Perhaps it takes a while for the chain reaction to produce a visible result in the horse, but it is still just a bunch of collisions, an inevitable chain of cause and effect. To put it another way, given the immutable laws of physics, the distribution and motion of atoms right now will make everything in the future utterly inevitable and necessary. It was apparently to avoid this that the Epicureans posited what they called a klinamen, or swerve. The idea is not found in our extant evidence for Epicurus, though it does seem to have been his idea. Lucretius discusses it in some detail. According to this notorious doctrine, atoms do not in fact always fall straight down, as I suggested a few episodes ago. That's mostly what happens, but occasionally an atom will apparently randomly shift slightly sideways. Lucretius gives two reasons for thinking this. One is that if all atoms only fell down, then the world would never arise because the atoms would never start to collide with one another. They would be like raindrops, hurtling next to each other in the void, all at the same speed. But this is probably not the real reason. After all, the Epicurean world is eternal, so there need never have been a moment where the atoms were not already colliding and moving in all directions. So they don't need to start colliding. The real motivation for the swerve is probably the second reason, avoiding the consequence that everything is necessary. Now one needs to be careful here. The mere presence of randomness in a physical system doesn't really help explain the power of choice. If what I am worried about is whether I am in control of my own actions, or whether my actions are instead induced by atomic motions, of which I am not even aware, then the swerve is no comfort at all. It will just turn out that the atomic motions that determine my action are sometimes random, rather than deterministic. But who cares about that? The point is to put me in control, not to have my actions ultimately trace back to random things out of my control. For this reason, it would be nice if the Epicureans were not saying, for instance, that each choice I make actually involves a swerving atom. Instead, they are just saying that the universe contains indeterminism. This is simply intended to show that human actions are not necessary and inevitable events, since there are no necessary and inevitable events in an indeterministic world. One reading of Lucretius on the swerve would support this. He doesn't seem to say that choices are swerves, or vice versa. Rather, he draws an analogy. Just as atoms can move by themselves when they swerve, so we can move by ourselves when we make choices. Nonetheless, it seems clear that any choice I make, any action I perform, must involve atomic motions, whether swerving or not. After all, there is nothing in the world apart from atoms in a void. This might lead us to say that choices, along with anything else you might care to name, are not real, except insofar as they are identical with atoms and their motions. That may be a consequence that the pre-Socratic Democritus drew from his atomism. He said, According to this fragment, Democritus apparently wanted to eliminate the properties we actually experience, like taste and colour, or at least treat them as merely conventional. An adequate scientific account of the universe could dispense with talk of such properties. You might think the Epicureans would follow suit, being atomists themselves, but instead they stoutly resist Democritus's sentiment, insisting that all these properties are absolutely real, though they may depend on atomic motions. This will go for human choices just as much as for colours and tastes. In another area of their philosophy, though, the Epicureans were happy to embrace a different kind of conventionalism. They did so in order to explain human society and language, a theme Lucretius takes up in the fifth book of his poem. With characteristically vibrant images, Lucretius gives a wholly naturalistic account of the origins of human political arrangements. Earlier in the book, he has already explained how animals arose, giving a theory reminiscent of the prezocratic philosopher Empedocles. As with Empedocles, Lucretius is often given credit for anticipating Darwinian evolutionary theory. He has explained that animals first arose through random atomic entanglements and propagated insofar as they were fit to survive. For instance, animals with no generative organs could not produce children, and died after one generation. In much the same way, human society grows out of a long and painful process. In the beginning, as Lucretius vividly describes, humans were in a kind of state of nature. Only once they developed the rudiments of trust and cooperation could they advance beyond the most primitive condition in which each man fights for his own survival. It was at this same time that humans first developed language. Lucretius too was simply a conventional advance on natural tendencies. Primitive man would naturally have communicated by grunts and gestures, something Lucretius illustrates by pointing out that children too young to talk articulately just point at whatever they want. Animals too can communicate with rudimentary noises, as we can see from the different noises made by dogs when they are angry, frightened, or caring for their pups. are simply a more refined use of the same capacity. So far so good, but next Lucretius qualifies the optimistic account of progress he's been giving so far. Once language and human cooperation are on the scene, the next step is the development of cities, of political rule, and of money. This is the breeding ground for the unnecessary desires against which the wise Epicurus warned. In the struggle to satisfy these desires, society begins to slide back into violence. A kind of second social contract is needed to restore order, and this explains the imposition of the laws that govern our society today. One wonders what Lucretius might have made of the civil wars that tore apart Roman society in this first century BC. A sign, perhaps, that society was preparing to backslide, having failed to heed Epicurus' warning that honor and power are poison chalices. It's almost a cliché to note that Epicureanism appeared in Greek society, and then reappeared in Roman society, at times of great upheaval. The post-Aristotelian Hellenistic schools emerged just after Alexander the Great achieved domination over Greece. The confident independence of city-states like Athens and Sparta, so recently centres of empire, was upset for good. From this point on, the political situation of the Greek cities was usually just a matter of which foreign power was calling the shots. The Macedonians? The Romans? Either way, an intelligent aristocrat was bound to seek out a philosophy of reassurance, both against the uncertainty of his circumstances, and against his newfound impotence. Likewise, in the first century BC, the Roman Republic fell, tearing power, if not wealth and noble lineage, from the hands of the senatorial class. Was Epicureanism successful because it could offer reassurance in times of upheaval? If so, it's appropriate that Lucretius' poem caused some upheaval of its own, when it was rediscovered in the early fifteenth century, after going unread and nearly being lost in late antiquity and the Middle Ages. Once unearthed, On the Nature of Things inspired such heavyweights as Machiavelli, who copied it out by hand, Gassendi, who adopted many of its doctrines, and Montaigne, who quotes it frequently in his essays. With any luck, we'll get to them all eventually. In the more immediate future, we will be turning to the main course in our feast of Hellenistic philosophy, the Stoics. Before that, though, we will indulge in one last Epicurean pleasure, an interview with one of the leading scholars of Epicurus and his legacy. I hope you'll still have enough appetite for this topic to join me as I talk to James Warren next time on The History of Philosophy Without Any Gaps. Thank you.