Titus Lucretius Carus was a Roman poet and philosopher active in the mid-first century BCE. A follower of Epicurus, little is known of his life. Fortunately, his epic philosophical poem De Rerum Natura (On the Nature of Things), comprising some 7,400 dactylic hexameters, survived into modern times. Luckily it was rediscovered in 1417 after having been believed lost for some 500 years during the Middle Ages. This epic poem has moments of clarity that line up with modern scientific findings, but other lines are clearly far from our understanding today of how the universe works.
A remarkable exposition of the beliefs and inferences underlying Epicureanism, De Rerum Natura propounds an atomistic mechanical worldview while at the same time denying that supernatural influences exist. This didactic poem was revered by such diverse historical figures as Niccolò Machiavelli, Moliere, John Locke, Isaac Newton, Robert Boyle, Michel de Montaigne, and George Santayana. A copy appeared in Ben Franklin's library, and Thomas Jefferson owned five Latin editions as well as English, Italian, and French translations.
I will take a quick look at some of the teachings found within Lucretius' elucidation of Epicureanism. Although the ideas presented had surely evolved during the two hundred years separating Epicurus and Lucretius, De Rerum Natura is regarded as the foremost contemporaneous account of Epicurean philosophy.
Linus Pauling described Chemistry as "the science of substances: their structure, their properties, and the reactions that change them into other substances." The following are combined quotes from Book I of De Rerum Natura, with modern terminology inserted with appropriate caution[*]:
"Matter is composed partly of atoms, and partly of molecules, which are combinations of atoms. Many things have atoms in common, just as letters of the alphabet appear in many different words. The reaction of atoms with other atoms can form clearly distinct chemicals."
Despite the 2,000 years separating these descriptions, it would appear that in the big picture, Epicurean atomism and modern chemistry sit quite comfortably together. Linus Pauling and Titus Lucretius Carus clearly agree in regards to chemistry.
The great theoretical physicist John Archibald Wheeler took the entire universe, from the quantum realm to the great ideas of cosmology, as his bailiwick. He was fond of saying "Time is Nature's way of keeping everything from happening at once," a phrase used in a different context by filmmaker Woody Allen. It expresses that we have no idea what time is, but can only see its effects. Compare Wheeler's famous quote with a quote from Lucretius[*]:
"Even time exists not of itself; but makes sense of things that happened long ago, that are happening now, and that shall happen in the future."
This worldview of mechanical atomism drew Lucretius to a view of time not as a Ding an sich (thing as itself), but rather as an ordering principle with an unknown mechanism.
One more set of quotes is of considerable interest. In an atomistic mechanical universe, Lucretius could not explain free will — as also noted by Newton and others, there seemed a conflict between a deterministic universe and free will. To resolve this conflict, he offered the following:
"The atoms must a little swerve at times — but only a bit, lest we notice impossible motions which are refuted by fact."
This teaching is not far from a quote from Heisenberg: "It is impossible to simultaneously measure the present position while also determining the future motion of a particle." Lucretius' swerve results in the same kind of uncertainty that Heisenberg's principle requires, and fundamentally not being able to see it is a prediction of the uncertainty principle.
De Rerum Natura also teaches of the emergence of composite properties, which differ from those of the atoms alone, of conservation of mass, of an analogy to zero-point motion, of an infinite universe containing many worlds with distinct forms of life, and of the absence of the aether. In short, Lucretius' teachings overlap many concepts of modern science.
Surely most of these correspondences are the result of selection effects, whereby we take special notice of poetic phrases that resonate with some aspect of modern science with which we are familiar. Indeed, much of De Rerum Natura is simply wrong — Newton caught up Lucretius on confusing the different types of infinity. And Lucretius denied the existence of centrifugal forces, as well as believing that gravity points down throughout the universe, rather than toward bodies of large mass.
Despite these difficulties, De Rerum Natura is a delight to read, offering superb poetry together with grand fun in seeing what remarkable ideas sprang forth from observations of nature interpreted by extraordinary minds!
[*] Here is the direct translation of these passages:
Bodies, again,
Are partly primal germs of things, and partly
Unions deriving from the primal germs.
Whilst many germs common to many things
There are, yet they, combined among themselves,
Can form new who to others quite unlike.