The Story of Western Science

by Susan Wise Bauer

  For the Greeks, too, supernatural and natural existed in the same space. In fact, it was the god-believing mathematician Thales who came up with what may be the first scientific theory: Despite its solid appearance, the entire universe is made of water. His writings on the subject are long lost, but Aristotle preserved their argument in the Metaphysics, 300 years later.

  Thales . . . stated [the foundational principle of the universe] to be water. (This is why he declared that the earth rests on water.) Perhaps he got this idea from seeing that the nourishment of all things is moist . . . and also because the seeds of all things have a moist nature; and water is the principle of the nature of most things.5

  Water (as it turned out) was the wrong explanation. But Thales’s theorizing is the earliest known attempt to peer inside the universal watchcase and see what else, independent of divine power, might be causing it to tick.

  Thales’s attempt to discover an underlying truth about the universe without reference to the gods (“Thales’s Leap,” biologist Lewis Wolpert calls it) was probably not the first Greek theory of its kind, but it is the first preserved by name. Thales’s actual works have disappeared, though. Thales’s Leap may be the first known scientific theory, but the Hippocratic Corpus—a collection of some sixty medical texts that explain disease without blaming or invoking the gods—is the first surviving book of science.

  The entire Corpus was once attributed to the shadowy Hippocrates himself, a fifth-century doctor who grew up on the tiny Greek island of Kos, just off the coast of Asia Minor. Plato tells us that Hippocrates taught aspiring doctors for a fee; the Corpus, now generally accepted as a collective project of his students and followers, preserves his lessons.6

  Many of Hippocrates’s contemporaries were priest-physicians, devotees of Aesculapius (son of Apollo, god of healing). To be cured by Aesculapius, a patient would travel to one of the temples of the god and spend the night in the abaton, the temple’s sacred dormitory, surrounded by the free-slithering snakes that represented the god’s presence. Sometime during the night, healing would take place. The serpents would lick the patient’s wounds and mend them, or the god would send a dream explaining how the illness should be treated. Or perhaps Aesculapius himself would appear to carry out the cure. “Gorgias of Heraclea had been wounded with an arrow in one of his lungs,” writes the Greek chronicler Pausanius:

  Within eighteen months the wound generated so much pus that sixty-seven cups were filled with it. He slept in the dormitory, and in a dream it seemed to him that the god removed the barb of the arrow with his lung. In the morning he went forth whole, with the barb of the arrow in his hands.7

  Hippocrates didn’t necessarily disbelieve in Aesculapius’s existence, but he was skeptical about the god’s role in illness. Instead, he looked to the visible world, the ordered cosmos, for explanations. Diseases were not caused by angry deities, and they did not need to be cured by a benevolent one. Even epilepsy, long held to be a sacred condition inflicted by demons or divine possession, was “no more divine nor more sacred than other diseases, but has a natural cause.” The only reason to chalk up illness to the will of a god is ignorance: “This notion of its divinity,” Hippocrates says tartly, “is kept up by men’s inability to comprehend it.”8

  Hippocrates blamed stomach upsets, fevers, epilepsy, plagues, and illnesses of all kinds on imbalance—too much or too little of one of the four fluids, or “humors,” that course through the human body. When these four fluids (bile, black bile, phlegm, and blood) exist in their proper proportions, the body is healthy. But any number of natural factors might throw them out of whack. For Hippocrates, the chief causes of unbalanced humors were winds (hot winds, for example, caused the body to produce far too much phlegm) and water (drinking stagnant water could lead to an overabundance of black bile). The recommended treatment: restore the body’s balance. Purges and bleeds were prescribed to get rid of excess humors. Herbs (rue, mustard, fennel, stinging nettle) helped to draw out some humors and renew others. Sick men and women were often sent to different climates, away from the winds and waters that were deranging their natural harmonies.9

  Like Thales’s theories, Hippocrates’s explanations were wrong. But half the time, entirely by accident, his methods worked. Avoiding marshy, stagnant water did improve health. Shifting from a crowded, epidemic-afflicted city to a breezy coastal town could bring recovery from an illness. Light nutritious meals were helpful to feverish patients—much more helpful than a long onerous journey to the nearest abaton and an uncomfortable night spent with snakes.

  While the temples of Aesculapius didn’t immediately go out of business, Hippocratic methods slowly gained traction—so much traction that in the eighteenth century, physicians were still purging, bleeding, and sending their patients to the seaside. The Hippocratic worldview even lingers today. I know perfectly well that a cold is a viral infection, but I still find myself yelling, “Don’t go outside without a coat or you’ll catch cold!” as my sons bound into a windy winter morning clad only in T-shirts and shorts.

  Thus the Hippocratic Corpus stands not only as the first surviving scientific writing, but the first recorded triumph of natural methods over the unearthly.

  To read relevant excerpts from The Corpus, visit http://susanwisebauer.com/story-of-science.

  HIPPOCRATES

  (ca. 460–370 BC)

  On Airs, Waters, and Places

  The nineteenth-century Francis Adams translation, one of the first done for English-speaking lay readers, is still readable and is available both in print and as an e-book. The Adams translation includes On Airs, Waters, and Places, along with the Aphorisms, The Oath of Hippocrates, and several other works, collected together as The Corpus. Editions include

  The Corpus, Kessinger Legacy Reprint (paperback, 2004, ISBN 978-1419107290).

  The Corpus, Library of Alexandria (e-book).

  The Corpus, with foreword by Conrad Fischer, Kaplan Classics of Medicine (e-book and paperback).

  The Adams translation of On Airs, Waters, and Places alone is available online in multiple places.

  A more modern translation is included in the Penguin Classics paperback Hippocratic Writings, translated by John Chadwick and W. N. Mann, with an introduction by G. E. R. Lloyd (paperback, 1983, ISBN 978-0140444513). The sentence structure is slightly easier to follow, but the two translations are very similar.

  TWO

  Beyond Man

  The first big-picture accounts of the universe

  Everything consists of the atoms . . . and there is nothing else.

  —Plutarch, on Democritus

  All men, Socrates, who have any degree of right feeling do

  this at the beginning of every enterprise great or small—

  they always call upon the gods.

  —Plato, Timaeus, ca. 360 BC

  Hippocrates and his followers were, without doubt, doing science. They looked to natural factors to explain the natural world, and their calling required more study than piety, more knowledge than faith.

  But they still had no capacity to peer inside the mechanism.

  The four humors had never been seen. The effects of waters and winds upon them had never been tested or proved. The human body still presented an impermeable surface to its examiners; the Greek physicians could describe its anatomy reasonably well, but the processes that went on within it were sealed away from their view. So instead of looking more closely,* Hippocrates and his followers tried to reason their way in. Their favorite analytical tool was the analogy: The eye is like a lantern, so it must contain fire. The internal organs are like copper vessels that hold humors; therefore they must be connected by a system of tubing that allows humors to shift from one organ to another.1

  This method of doing science had almost nothing to do with observation. In the absence of scientific tools, without a shared scientific vocabulary, lacking the most basic agreement over the foundational principles of the universe, the Greeks created elaborate hypothe
tical structures and then fitted symptoms carefully into them. Upset stomach? The tubing between your internal organs must be blocked, creating a buildup of humors. Treatment: flush the tubing with a purge, just as a plumber would flush a blocked pipe.

  The Hippocratic doctors, characterized by the professional myopia that still afflicts many physicians, did not look very far beyond the body’s immediate surroundings. But in the centuries after Hippocrates, Greek thinkers began to speak and write in similar ways (naturalistic ways, driven by analogies) about phusis: the ordered universe, the whole natural realm.

  Phusis, often translated simply as “nature,” encompassed much more than the natural world as we would now think of it. The ordered universe consisted of the earth and men. To study phusis was to study both politics and plants, the soul and the stars. The Greeks inhabited a fluid and unbounded intellectual landscape; speculations about the composition of the sea and sky mingled seamlessly with political philosophy.2

  Lacking any tradition of close observation, in the absence of any scientific tools that would allow them to pick apart a phenomenon into its component parts, the Greek thinkers instead attempted to explain phusis in its entirety, from origin to its present form. They were armchair time travelers, creating elaborate story lines for the universe. The monists believed that it all began with a single underlying element, one sort of stuff, containing within itself the principle of its own change: “This, they say, is the element and this the principle of things,” Aristotle wrote much later of the monists, “some entity . . . from which all other things come to be.” Thales, one of the earliest monists, had proposed water; the sixth-century philosophers Anaximenes and Heraclitus suggested air and fire, respectively; Anaximander, around 575 BC, proposed something called “the indefinite,” a thing that has itself no characteristics but contains opposite qualities that separate, producing change. The pluralists, on the other hand, were in favor of multiple underlying elements; Empedocles, around 460 BC, suggested four—earth, air, fire, and water—an arrangement widely adopted by other thinkers.3

  And then there were the atomists, most notably the shadowy Leucippus and his much-better-known pupil Democritus, both of them teaching and writing in the last quarter of the fifth century. “Leucippus . . . posited limitless and eternally moving elements, the atoms,” the philosopher Simplicius explains. Democritus expanded on his master’s theory; these atoms “are so small that they escape our senses. . . . From them, as from elements . . . the visible and perceptible masses” are formed.4

  As it turned out, this was more or less true.

  The atomists are often celebrated as eerily farsighted and discerning. Actually, they were no more gifted than the monists or pluralists; it just so happened that, like Hippocrates, they accidentally hit on some elements of the truth. “These early atomists may seem wonderfully precocious,” remarks physicist (and Nobel laureate) Steven Weinberg, “but it does not seem to me very important that the [monists] were ‘wrong’ and that the atomic theory of Democritus and Leucippus was in some sense ‘right.’ . . . How far do we progress toward understanding why nature is the way it is if Thales or Democritus tells us that a stone is made of water or atoms, when we still do not know how to calculate its density or hardness or electrical conductivity?”5

  In other words, the watchcase was still firmly closed; these early science writers were theorizing with no way to check their results. And we cannot even read their actual words, because their texts, like Thales’s writings, have all been lost. Their speculations are preserved only in the summaries and studies written by others, long after the fact. Sextus Empiricus, who gives a detailed summary of Democritus’s teachings in his work Against the Mathematicians, lived six hundred years later; Simplicius, one of the few to quote Leucippus directly, was born a millennium after his subject.

  But together, the monists, pluralists, and atomists† took a critical step forward. All of them affirmed the same principle: Phusis, like human illness, could be explained in purely material terms. If the atomists stand a little to the fore, it is only because Democritus was even more insistent than his colleagues that the universe consisted of nothing but atoms and what he called “the empty”—the place in which atoms rushed about, collided and intertwined by chance, and separated by coincidence. There were gods in Democritus’s world, but they too were made up of atoms; they too were subject to the laws of nature; they created nothing, and they too would eventually be dissolved. There was no plan. There was no design. There were simply atoms, moving randomly in the empty.

  Democritus cast the gods out of beginnings. His explanations for the existence of the universe were all materialistic; and like materialistic explanations ever since, they inspired vigorous opposition.6

  The most vigorous, and the most influential, came two generations after Democritus, from the long-lived Athenian philosopher Plato. Without the gods, objected Plato, ethics were doomed. Without godly origin, the state would disintegrate. Without supernatural creation, human morality would vanish. Therefore, phusis might be comprehended by the senses, but its beginnings must be explained with reference to the divine.7

  So in the Timaeus, written late in his life, Plato offered his own sketch of the universe and how it works—the first self-consciously big-picture neoscientific treatise, the first known attempt to offer a theory of everything. It is a hybrid work, beginning with the origins of the universe at the hands of a divine creator—a divine force, an unknown Craftsman—and then moving from origins to an explanation of the universe’s present function that has no reference to the divine. Plato lived in a world where it was no longer possible to ascribe the rising of rivers and the motions of the moon to the will of gods. Yet he could not imagine a universe that had always been, or a beginning that was not sparked by the divine.

  Looking around at the ordered world, Plato sees design and beauty; this, he reasons, must come from a mind, from an intelligence. So he begins with an account of a Demiurge (a being who fashions what we see from materials that already exist) and the shaping of a good, spherical universe out of disorderly, irregular matter. This good universe exists first, uncorrupted and perfect, in the mind of the Demiurge; as it comes into physical being, it slips very slightly away from this Ideal, taking shape as a visible and inferior Copy, a physical shadow of the original Reality.

  This physical universe consists of four elements—earth and fire the most elemental, with air and water as a bond between them. Human beings, living in the corporeal universe and in some ways mirroring its structure (as water circulates through the earth, so blood circulates through the body), can understand it through the senses: touch, smell, sight, hearing.

  And in this perception, the Craftsman has no part.8

  This is, of course, a simplification of the Timaeus. “Of all the writings of Plato, the Timaeus is the most obscure and repulsive to the modern reader,” begins the introduction to Benjamin Jowett’s classic translation of Plato’s Dialogues, and he does not overstate the dialogue’s complexity. Striving to describe physical phenomena in a language that had been devoted to poetry and philosophy, Plato writes so obliquely that it is often a struggle to figure out the topic of a given sentence, let alone its conclusion. And interwoven with his descriptions of how we sense and interpret are long discourses on philosophical distinctions (for example, between what always is and never becomes and what becomes and never is), a bizarre explanation of why the universe doesn’t have feet but we do, and the story of the lost civilization of Atlantis.

  Yet the Timaeus affected the practice of Western science for the next two thousand years. Plato divided origins from observation, creation from the explanations of everyday phenomena. He acknowledged the importance of the senses in the study of the world around us—and, like Hippocrates, opened up an ever-widening space in which science could be practiced without appeal to the supernatural.

  This was a great gift to the newborn field of science. But Plato’s bequest carried with it a fatal infectio
n. Yes, man can understand the physical world through the senses. But since physical reality is a shadow of the ideal, physics is always subordinate to metaphysics. Philosophy struggles to understand the Ideal from which the world has declined. Science merely uses observation to understand the declined shadow itself. And so science can never lead to truth; it must always sit at philosophy’s feet, willing to receive correction.

  To read relevant excerpts from the Timaeus, visit http://susanwisebauer.com/story-of-science.

  PLATO

  Timaeus

  (ca. 360 BC)

  Benjamin Jowett’s nineteenth-century translation is still widely reprinted and is clear and accessible to modern readers. Although it is not included in all editions of Plato’s collected Dialogues, it can be found in

  The Dialogues of Plato in Four Volumes, vol. 2, Charles Scribner’s Sons (e-book, 1892).

  Dialogues of Plato: Translated into English with Analyses and Introduction, Cambridge University Press (paperback, 2010, ISBN 978-1108012102).

  A modern translation can be found in

  Peter Kalkavage, trans., Plato’s Timaeus, Focus Publishing (paperback, 2001, ISBN 978-1585100071).

  Unlike the Greek of Hippocrates, which deals with things (water, phlegm, purges, bellies), Plato’s Greek consists largely of abstract terms that cannot easily be translated by single words. He deals with matters of being and existence, not diagnosis and prescription; his vocabulary is obscure and/or archaic; and on top of that, he is fond of wordplay, sly linguistic jokes, and puns. As a result, translations differ markedly. Here is Jowett’s rendering of a passage from the first part of the Timaeus:

  Why did the Creator make the world? He was good, and desired that all things should be like himself. Wherefore he set in order the visible world, which he found in disorder.9