In my last posting, I marveled at the understanding of the cosmos we have achieved in the 21st century. I hope you did too. But before we get too swollen-headed, I suggest that we look into what the ancients knew about the subject. Let's start with a brief excursion into history.
Our first stop is the year 54 BCE, where we encounter the Epicurian poet Titus Lucretius Carus, who has just finished the 7400-line poem De Rerum Natura (On the Nature of Things). In it, largely following the ideas of Epicurus and his predecessors, Lucretius sums up an understanding of the physical world held by many of the cognoscenti of his time, and gives advice on how to live in that world. The poem is well received by such contemporary lights as Cicero and Virgil.
Our next stop is 1417 CE. By this date, De Rerum Natura has been missing for about a thousand years, known only through references to it in other ancient literature. Poggio Bracciolini, a papal official with a hobby of searching for classical books long "lost" in monasteries and elsewhere, stumbles across the only surviving copy of the work. Despite the poem's dramatically un-Christian philosophy and world view, bibliophile/humanist Bracciolini makes sure that it is copied and recopied, and widely distributed.
Now we return to 2011, when Stephen Greenblatt publishes The Swerve: How the World Became Modern, a fascinating book about the rediscovery of De Rerum Natura and its effect on thinkers in the 15th century and later. The eighth of its eleven chapters discusses in great detail the model of the world Lucretius propounded. That chapter is my subject today.
A 4300-word review of The Swerve in the New York Review of Books derisively dismissed this lone chapter in seven words: "a disappointingly dry series of bullet points." That dismays me, for to me the chapter is the very crux of Greenblatt's book. The rest is an excellent historical read, but nothing like the page turner I found in Chapter 8.
To back up this assertion, I can do no better than to quote at length from Greenblatt's "dry bullet points," but still in very abridged form. See if you agree with me that Lucretius' model of the world is so close to ours that it takes your breath away.
--Everything is made of invisible particles. Immutable, indivisible, invisible, and infinite in number, they are constantly in motion, clashing with one another, coming together to form new shapes, coming apart, recombining again, enduring.
--The elementary particles of matter . . . are eternal. Time is not limited--a discrete substance with a beginning and an end--but infinite. The invisible particles from which the entire universe is made, from the stars to the lowliest insect, are indestructible and immortal, though any particular object in the universe is transitory.
--The elementary particles are infinite in number but limited in shape and size. They are like the letters in an alphabet, a discrete set capable of being combined in an infinite number of sentences. . . . As not all letters or all words can be coherently combined, so too not all particles can combine with all other particles in every possible manner. Some . . . easily hook onto others; some repel and resist one another.
--All particles are in motion in an infinite void. Space, like time, is unbounded. There are no fixed points, no beginnings, middles or ends, and no limits. Matter is not packed together in a solid mass. There is a void in things, allowing the constitutive particles to move, collide, combine and move apart.
--The universe has no creator or designer. The particles themselves have not been made and cannot be destroyed. The patterns of order and disorder in the world are not the product of any divine scheme.
--Everything comes into being as a result of a swerve. [T]he particles do not move in lockstep in a preordained single direction. Instead, "at absolutely unpredictable times and places they deflect slightly from their straight course . . ." The position of the elementary particles is thus indeterminate.
--The swerve is the source of free will. In the lives of all sentient creatures, human and animal alike, the random swerve of elementary particles is responsible for the existence of free will.
--Nature ceaselessly experiments. There is no single moment of origin, no mythic scene of creation. All living beings, from plants and insects to higher mammals and man, have evolved through a long, complex process of trial and error. The process involves many false starts and dead ends, monsters, prodigies, mistakes, creatures that were not endowed with all the features that they needed to compete for resources and to create offspring. Creatures . . . enable[d] to adapt and reproduce will succeed . . . until changing circumstances make it impossible for them any longer to survive. The successful adaptations, like the failures, are the result of a fantastic number of combinations that are constantly being generated (and reproduced or discarded) over an unlimited expanse of time.
--The universe was not created for or about humans. . . . The fate of the entire species . . . is not the pole around which everything revolves. Indeed, there is no reason to believe that human beings as a species will last forever.
--Humans are not unique. They are part of a much larger material process that links them not only to all other life forms but to inorganic matter as well. . . . We are made of the same stuff that everything else is made of.
--Human society began not in a Golden Age of tranquility and plenty, but a primitive battle for survival. . . . [T]he ability to form bonds and live in communities governed by settled customs developed slowly. . . . The arts of civilization [were] not given to man by some divine lawmaker but painstakingly fashioned by the shared talents and mental power of the species . . .
I omit the remaining bullet points not because they are unimportant but because they are not so much about the physical world. They deal with the nature of the soul; with death; with religion, which Lucretius calls delusive and cruel; and with the pursuit of happiness as the highest goal of life. (Greenblatt claims that "pursuit of happiness" entered the Declaration of Independence via Jefferson's readings of Lucretius.)
Returning to the bullet points that I did summarize: don't you agree that the similarity of Lucretius' model of the physical world to ours is astounding? We all know that the ancient world descended into the Dark Ages, from which it took a millennium to start recovering. But I for one had no inkling that, despite the many remarkable results of the ensuing scientific revolution, we have returned so nearly to a model described in antiquity!
Some critics [1, 2] have taken Greenblatt to task for, they say, overemphasizing the effect that the rediscovery of De Rerum Natura had on the Renaissance, as expressed in the subtitle How the World Became Modern. One of them [2] has caviled about what he sees as Greenblatt's adherence to an "old humanist myth" about the Renaissance, that it was a sudden upwelling of ancient knowledge. (Greenblatt is a renowned scholar of the English Renaissance and of Shakespeare's place in it.) I think this is absurd quibbling. Greenblatt wasn't writing for scholars, but for lay readers like me. His book deservedly won the National Book Award and hit the New York Times best-seller list.