by Will Durant
THE cultural activity of Periclean Greece takes chiefly three forms-art, drama, and philosophy. In the first, religion is the inspiration; in the second it is the battleground; in the third it is the victim. Since the organization of a religious group presumes a common and stable creed, every religion sooner or later comes into opposition with that fluent and changeful current of secular thought that we confidently call the progress of knowledge. In Athens the conflict was not always visible on the surface, and did not directly affect the masses of the people; the scientists and the philosophers carried on their work without explicitly attacking the popular faith, and often mitigated the strife by using the old religious terms as symbols or allegories for their new beliefs; only now and then, as in the indictments of Anaxagoras, Aspasia, Diagoras of Melos, Euripides, and Socrates, did the struggle come out into the open, and become a matter of life and death. But it was there. It ran through the Periclean age like a major theme, played in many keys and elaborated in many variations and forms; it was heard most distinctly in the skeptical discourses of the Sophists and in the materialism of Democritus; it sounded obscurely in the piety of Aeschylus, in the heresies of Euripides, even in the irreverent banter of the conservative Aristophanes; and it was violently recapitulated in the trial and death of Socrates. Around this theme the Athens of Pericles lived its mental life.
I. THE MATHEMATICIANS
Pure science, in fifth-century Greece, was still the handmaiden of philosophy, and was studied and developed by men who were philosophers rather than scientists. To the Greeks higher mathematics was an instrument not of practice but of logic, directed less to the conquest of the physical environment than to the intellectual construction of an abstract world.
Popular arithmetic, before the Periclean period, was almost primitively clumsy.* One upright stroke indicated 1, two strokes 2, three 3, and four 4; 5, 10, 100, 1000, and 10,000 were expressed by the initial letter of the Greek word for the number—pente, deka, hekaton, chilioi, myrioi. Greek mathematics never achieved a symbol for zero. Like our own it betrayed its Oriental origin by taking from the Egyptians the decimal system of counting by tens, and from the Babylonians, in astronomy and geography, the duodecimal or sexagesimal system of counting by twelves or sixties, as still on our clocks, globes, and charts. Probably an abacus helped the people with the simpler calculations. Fractions were painful for them: to work with a complex fraction they reduced it to an accumulation of fractions having I as their common numerator; so was broken down into .1
Of Greek algebra we have no record before the Christian era. Geometry, however, was a favorite study of the philosophers, again less for its practical value than for its theoretical interest, the fascination of its deductive logic, its union of subtlety and clarity, its imposing architecture of thought. Three problems particularly attracted these mathematical metaphysicians: the squaring of the circle, the trisection of the angle, and the doubling of the cube. How popular the first puzzle became appears in Aristophanes’ Birds, in which a character representing the astronomer Meton enters upon the stage armed with ruler and compasses, and undertakes to show “how your circle may be made a square”—i.e., how to find a square whose area will equal that of a given circle. Perhaps it was such problems as these that led the later Pythagoreans to formulate a doctrine of irrational numbers and incommensurable quantities.* It was the Pythagoreans, too, whose studies of the parabola, the hyperbola, and the ellipse prepared for the epochal work of Apollonius of Perga on conic sections.2 About 440 Hippocrates of Chios (not the physician) published the first known book on geometry, and solved the problem of squaring the lune.† About 420 Hippias of Elia accomplished the trisection of an angle through the quadratrix curve.3 About 410 Democritus of Abdera announced that “in constructing lines according to given conditions no one has ever surpassed me, not even the Egyptians;”4 he almost made the boast forgivable by writing four books on geometry, and finding formulas for the areas of cones and pyramids.5 All in all, the Greeks were as excellent in geometry as they were poor in arithmetic. Even into their art geometry entered actively, making many forms of ceramic and architectural ornament, and determining the proportions and curvatures of the Parthenon.
II. ANAXAGORAS
It was part of the struggle between religion and science that the study of astronomy was forbidden by Athenian law at the height of the Periclean age.6 At Acragas Empedocles suggested that light takes time to pass from one point to another.7 At Elea Parmenides announced the sphericity of the earth, divided the planet into five zones, and observed that the moon always has its bright portion turned toward the sun.8 At Thebes Philolaus the Pythagorean deposed the earth from the center of the universe, and reduced it to the status of one among many planets revolving about a “central fire.”9 Leucippus, pupil of Philolaus, attributed the origin of the stars to the incandescent combustion and concentration of material “drawn onward in the universal movement of the circular vortex.”10 At Abdera Democritus, pupil of Leucippus and student of Babylonian lore, described the Milky Way as a multitude of small stars, and summarized astronomic history as the periodical collision and destruction of an infinite number of worlds.11 At Chios Oenopides discovered the obliquity of the ecliptic.11a Nearly everywhere among the Greek colonies the fifth century saw scientific developments remarkable in a period almost devoid of scientific instruments.
But when Anaxagoras tried to do similar work at Athens he found the mood of the people and the Assembly as hostile to free inquiry as the friendship of Pericles was encouraging. He had come from Clazomenae about 480 B.C., at twenty years of age. Anaximenes so interested him in the stars that when someone asked him the object of life he answered, “The investigation of sun, moon, and heaven.”12 He neglected his patrimony to chart the earth and the sky, and fell into poverty while his book On Nature was acclaimed by the intelligentsia of Athens as the greatest scientific work of the century.
It carried on the traditions and speculations of the Ionian school. The universe, said Anaxagoras, was originally a chaos of diverse seeds (spermata), pervaded by a nous, or Mind, tenuously physical, and akin to the source of life and motion in ourselves. And as mind gives order to the chaos of our actions, so the World Mind gave order to the primeval seeds, setting them into a rotatory vortex,* and guiding them toward the development of organic forms.13 This rotation sorted the seeds into the four elements—fire, air, water, and earth—and separated the world into two revolving layers, an outer one of “ether,” and an inner one of air. “In consequence of this violent whirling motion, the surrounding fiery ether tore away stones from the earth, and kindled them into stars.”14 The sun and the stars are glowing masses of rock: “The sun is a red-hot mass many times larger than the Peloponnesus.”15 When their revolving motion wanes, the stones of the outer layer fall upon the earth as meteors.16 The moon is an incandescent solid, having on its surface plains, mountains, and ravines;17 it receives its light from the sun, and is of all heavenly bodies the nearest to the earth.18 “The moon is eclipsed through the interposition of the earth . . . the sun through the interposition of the moon.”19 Probably other celestial bodies are inhabited like the earth; upon them “men are formed, and other animals that have life; the men dwell in cities, and cultivate fields as we do.”20 Out of the inner or gaseous layer of our planet successive condensations produced clouds, water, earth, and stones. Winds are due to rarefactions of the atmosphere produced by the heat of the sun; “thunder is caused by the collision of clouds, and lightning by their friction.”21 The quantity of matter never changes, but all forms begin and pass away; in time the mountains will become the sea.22 The various forms and objects of the world are brought into being by increasingly definite aggregations of homogeneous parts (homoiomeria)23 All organisms were originally generated out of earth, moisture, and heat, and thereafter from one another.24 Man has developed beyond other animals because his erect posture freed his hands for grasping things.25
These achievements—the foundation of
meteorology, the correct explanation of eclipses, a rational hypothesis of planetary formation, the discovery of the borrowed light of the moon, and an evolutionary conception of animal and human life—made Anaxagoras at once the Copernicus and Darwin of his age. The Athenians might have forgiven him these apergus had he not neglected his nous in explaining the events of nature and history; perhaps they suspected that this nous, like Euripides’ deus ex machina, was a device for saving the author’s skin. Aristotle notes that Anaxagoras sought natural explanations everywhere.26 When a ram with a single horn in the center of its forehead was brought to Pericles, and a soothsayer interpreted it as a supernatural omen, Anaxagoras had the animal’s skull cleft, and showed that the brain, instead of filling both sides of the cranium, had grown upward towards the center, and so had produced the solitary horn.27 He aroused the simple by giving a natural explanation of meteors, and reduced many mythical figures to personified abstractions.28
The Athenians took him good-humoredly for a time, merely nicknaming him nous.29 But when no other way could be found of weakening Pericles, Cleon, his demagogic rival, brought a formal indictment of impiety against Anaxagoras on the charge that he had described the sun (still to the people a god) as a mass of stone on fire; and pursued the case so relentlessly that the philosopher, despite Pericles’ brave defense of him, was convicted.* Having no taste for hemlock, Anaxagoras fled to Lampsacus on the Hellespont, where he kept himself alive by teaching philosophy.† When news was brought to him that the Athenians had condemned him to death, he said, “Nature has long since condemned both them and me.”33 He died a few years later, aged seventy-three.
The backwardness of the Athenians in astronomy was reflected in their calendar. There was no general Greek calendar: every state had its own; and each of the four possible points for beginning a new year was adopted somewhere in Greece; even the months changed their names across frontiers. The Attic calendar reckoned months by the moon, and years by the sun.34 As twelve lunar months made only 360 days, a thirteenth month was added every second year to bring the calendar into harmony with the sun and the seasons.35 Since this made the year ten days too long, Solon introduced the custom of having alternate months of twenty-nine and thirty days, arranged into three weeks (dekades) of ten (occasionally nine) days each;36 and as an excess of four days still remained, the Greeks omitted one month every eighth year. In this incredibly devious way they at last arrived at a year of 365 ¼ days.‡
Meanwhile a modest degree of progress was made in terrestrial science. Anaxagoras correctly explained the annual overflow of the Nile as due to the spring thaws and rains of Ethiopia.38 Greek geologists attributed the Straits of Gibraltar to a cleaving earthquake, and the Aegean isles to a subsiding sea.39 Xanthus of Lydia, about 496, surmised that the Mediterranean and the Red Sea were formerly connected at Suez; and Aeschylus noted the belief of his time that Sicily had been torn asunder from Italy by a convulsion of the earth.40 Scylax of Caria (521-485) explored the whole coast of the Mediterranean and the Black Sea. No Greek seems to have dared so adventurous a voyage of discovery as that which the Carthaginian Hanno, with a fleet of sixty ships, led through Gibraltar some 2600 miles down the west coast of Africa (ca. 490). Maps of the Mediterranean world were common in Athens at the end of the fifth century. Physics, so far as we know, remained undeveloped, though the curvatures of the Parthenon show considerable knowledge of optics. The Pythagoreans, towards 450, announced the most lasting of Greek scientific hypotheses—the atomic constitution of matter. Empedocles and others expounded a theory of the evolution of man from lower forms of life, and described the slow advance of man from savagery to civilization.41
III. HIPPOCRATES
The epochal event in the history of Greek science during the Periclean age was the rise of rational medicine. Even in the fifth century Greek medicine was in large measure bound up with religion, and the treatment of disease was still practiced by the temple priests of Asclepius. This temple therapy used a combination of empirical medicine with impressive ritual and charms that touched and released the imagination of the patient; possibly hypnosis and some form of anesthesia were also employed.42 Secular medicine competed with this ecclesiastical medicine. Though both groups ascribed their origin to Asclepius, the profane Asclepiads rejected religious aids, made no claim to miraculous cures, and gradually placed medicine upon a rational basis.
Secular medicine, in fifth-century Greece, took form in four great schools: at Cos and Cnidus in Asia Minor, at Crotona in Italy, and in Sicily. At Acragas Empedocles, half philosopher and half miracle man, shared medical honors with the rational practitioner Acron.43 As far back as 520 we read of the physician Democedes, who, born at Crotona, practiced medicine in Aegina, Athens, Samos, and Susa, cured Darius and Queen Atossa, and returned to spend his last days in the city of his birth.44 At Crotona, too, the Pythagorean school produced the most famous of Greek physicians before Hippocrates. Alcmaeon has been called the real father of Greek medicine,45 but he is clearly a late name in a long line of secular medicos whose origin is lost beyond the horizons of history. Early in the fifth century he published a work On Nature (peri physeos)—the usual title, in Greece, for a general discussion of natural science. He, first of the Greeks, so far as we know, located the optic nerve and the Eustachian tubes, dissected animals, explained the physiology of sleep, recognized the brain as the central organ of thought, and defined health Pythagoreanly as a harmony of the parts of the body.46 At Cnidus the dominating figure was Euryphron, who composed a medical summary known as the Cnidian Sentences, explained pleurisy as a disease of the lungs, ascribed many illnesses to constipation, and became famous for his success as an obstetrician.47 An unmerry war raged between the schools of Cos and Cnidus; for the Cnidians, disliking Hippocrates’ penchant for basing “prognosis” upon general pathology, insisted upon a careful classification of each ailment, and a treatment of it on specific lines. In the end, by a kind of philosophical justice, many of the Cnidian writings found their way into the Hippocratic Collection.
As we see Hippocrates in Suidas’ thumbnail biography, he appears as the outstanding physician of his time. He was born in Cos in the same year as Democritus; despite their far-separated homes the two became great friends, and perhaps the “laughing philosopher” had some share in the secularization of medicine. Hippocrates was the son of a physician, and grew up and practiced among the thousands of invalids and tourists who came to “take the waters” in the hot springs of Cos. His teacher, Herodicus of Selymbria, formed his art by accustoming him to rely upon diet and exercise rather than upon drugs. Hippocrates won such repute that rulers like Perdiccas of Macedon and Artaxerxes I of Persia were among his patients; and in 430 Athens sent for him to try his hand at staying the great plague. His friend Democritus shamed him by completing a century, while the great physician died at the age of eighty-three.
Nothing in medical literature could be more heterogeneous than the collection of treatises anciently ascribed to Hippocrates. Here are textbooks for physicians, counsels for laymen, lectures for students, reports of researches and observations, clinical records of interesting cases, and essays by Sophists interested in the scientific or philosophical aspects of medicine. The forty-two clinical records are the only examples of their kind for the next seventeen hundred years; and they set a high standard of honesty by confessing that in sixty per cent of the cases the disease, or the treatment, proved fatal.48 Of all these compositions only four are by general consent from the pen of Hippocrates—the “Aphorisms,” the “Prognostic,” the “Regimen in Acute Diseases,” and the monograph “On Wounds in the Head”; the remainder of the Corpus Hippocraticum is by a variety of authors ranging from the fifth to the second century B.C.49 There is a fair amount of nonsense in the assortment, but probably not more than the future will find in the treatises and histories of the present day. Much of the material is fragmentary, and takes a loose aphoristic form verging now and then upon Heracleitean obscurity. Among the “Apho
risms” is the famous remark that “Art is long, but time is fleeting.”50
The historical role of Hippocrates and his successors was the liberation of medicine from both religion and philosophy. Occasionally, as in the treatise on “Regimen,” prayer is advised as an aid; but the page-by-page tone of the Collection is a resolute reliance upon rational therapy. The essay on “The Sacred Disease” directly attacks the theory that ailments are caused by the gods; all diseases, says the author, have natural causes. Epilepsy, which the people explained as possession by a demon, is not excepted: “Men continue to believe in its divine origin because they are at a loss to understand it. . . . Charlatans and quacks, having no treatment that would help, concealed and sheltered themselves behind superstition, and called this illness sacred in order that their complete ignorance might not be revealed.”51 The mind of Hippocrates was typical of the Periclean time spirit—imaginative but realistic, averse to mystery and weary of myth, recognizing the value of religion, but struggling to understand the world in rational terms. The influence of the Sophists can be felt in this move for the emancipation of medicine; and indeed, philosophy so powerfully affected Greek therapy that the science had to fight against philosophical as well as theological impediments. Hippocrates insists that philosophical theories have no place in medicine, and that treatment must proceed by careful observation and accurate recording of specific cases and facts. He does not quite realize the value of experiment; but he is resolved to be guided by experience.52
The natal infection of Hippocratic medicine with philosophy appears in the once famous doctrine of “humors.” The body, says Hippocrates, is compounded of blood, phlegm, yellow bile, and black bile; that man enjoys the most perfect health in whom these elements are duly proportioned and mingled; pain is the defect or excess of one “humor,” or its isolation from the rest.53 This theory outlived all the other medical hypotheses of antiquity; it was abandoned only in the last century, and perhaps survives by transmigration in the doctrine of hormones or glandular secretions today. Since the behavior of the “humors” was considered subject to climate and diet, and the most prevalent ailments in Greece were colds, pneumonia, and malaria, Hippocrates (?) wrote a brief treatise on “Airs, Waters, Places” in relation to health. “One may expose oneself confidently to cold,” we are told, “except after eating or exercise. . . . It is not good for the body not to be exposed to the cold of winter.”54 The scientific physician, wherever he settles, will study the effects, upon the local population, of the winds and the seasons, the water supply and the nature of the soil.
