Lucretius was a Roman poet and philosopher born in Samos (an Athenian colony) in 341 BC. He would come to live in Italy, where he was surrounded by constant war and strife. Lucretius would embrace the philosophy of Epicurus (Epicureanism) which emphasized tranquility and peace of mind for attaining happiness. In his poem On the Nature of Things, Lucretius fleshes out Epicurus’ philosophy in order to create a scientific understanding of the world which is naturalistic, mechanistic, and atomistic (composed on indivisible units of matter known as atoms). Like Epicurus, Lucretius believed that religion caused a lot of unnecessary hardships for people, and he denied the existence of anything supernatural. Also, Lucretius embraced Epicurus’ belief that death is the end of life, and therefore there is nothing to fear.

Italy in the 1st century BC was a time of constant civil war and unrest, political assassinations, public executions, conspiracies and revolts. Within this world, Lucretius became enamored with Epicurus and his philosophy, which emphasized the possibility of attaining inner peace through philosophy, modesty, and friendship. In On the Nature of Things, Lucretius is disgusted by the events going on around him, exclaiming “After a while the life of a fool is hell on earth.” He came to the conclusion that “All life is a struggle in the dark,” and through his philosophical poem hoped to be able to illuminate a path to enlightenment laid out by Epicurus.

Lucretius believed that religion, in particular supernatural beliefs, caused people a lot of unnecessary hardship. “So powerful is religion at persuading to evil,” he explains, seeing the belief in Gods and superstition as a cause of both anxiety and war. He believed the divine should be something that lifts the individual to a higher plane, not a source of fear. In his poem , the Gods are described living a life of tranquility, the same that can be achieved by humans who live a life of contemplation. Epicurus is a hero to Lucretius, one who helps man conquer his fears, desires, and misunderstandings.

For Lucretius, the world can be explained in naturalistic terms. He didn’t see it making sense that a divine intelligence would have created a world where humans must endure so much hardship. Rather, the world came into being through the random collision and combination of atoms flying through space. He thinks those who see the human eye, for example, as having been intelligently designed are mistaken. Just as a bed is only made to improve sleep, likewise sight must have naturally developed, and then the human eye evolved to improve this function. Lightning and thunder are natural occurrences, not the wrath of Zeus. He makes fun of this traditional belief, saying if lightning bolts are really hurled by Zeus, why does he sometimes miss his mark, or even destroy his own temples?

Lucretius describes how the world originally gave rise to early life forms, and those best suited to the environment while the rest died out. As such, he is seen as a precursor to Darwin and his theory of natural selection and the survival of the fittest. He also explains developments in human culture and society. Fire, rather than being a gift from Prometheus, was found through the natural occurrence of forest fires. Languages was intuitively developed upon the realization that producing sounds is a good way to communicate.

In Lucretius’ cosmology (i.e. understanding of the world), it is impossible for anything to come into being from nothing or be destroyed. Rather, the universe has always existed and is infinite. Within such a universe, many worlds form and are dissolved through the randomness of atomic motion. For Lucretius, the earth is not the center of the universe. In this way, he undermines the religious belief that we have been divinely created as something special. Lucretius sees the world as constantly in motion, and likens it to a flock of sheep which when seen from a distance appears as one stable entity. He avoids determinism and is able to account for free will by explaining the existence of “swerve” in the direction of atoms in motion.

Like the rest of the universe, the soul is also seen as being composed of atoms, which disperse upon death. In this way, like Epicurus, Lucretius’ denies the traditional mythological understanding of there being an afterlife, and instead explains that death is simply the end of life. For this reason, he explains that there is no reason to fear death. He explains that the endless state of non-existence which is death is similar to the state of non-existence which occurs before we are born, and since we do not fear what happened before we are born, likewise there is no reason to fear what happens after we are dead (this is known as the symmetry argument).

Throughout On the Nature of Things, Lucritus describes a world of trees and water and scenery, which contrasts the beauty of nature and the country with the bloodshed and chaos created by humans in their cities. Through his poetry, he creates a beautiful vessel for Epicurean philosophy which is both critical of humanity, as well as provides a path of enlightenment for the individual who embraces tranquility . His poem would influence poets such as Virgil, Milton and Walt Whitman, while his scientific understanding of the world would influence both the early atomists as well as the evolutionists of modern Europe. His understanding of an infinite universe would serve as the basis for the scientific theories of Newton, as well as modern philosophies such as Spinoza’s Ethics and Leibniz’ Monadology.