The Life of Greece

by Will Durant

  CHAPTER XXI

  The Zenith of Philosophy

  I. THE SCIENTISTS

  COMPARED with the bold advance of the fifth century, and the revolutionary achievements of the third, science in the fourth marked time, and contented itself, in great part, with recording its accumulations. Xenocrates wrote a history of geometry, Theophrastus a history of natural philosophy, Menon a history of medicine, Eudemus histories of arithmetic, geometry, and astronomy.1 The problems of religion, morals, and politics appearing to be more vital and pressing than the problems of nature, men turned with Socrates from the objective study of the material world to a consideration of the soul and the state.

  Plato loved mathematics, dipped his philosophy into it deeply, dedicated the Academy to it, almost, in Syracuse, gave a kingdom for it. But arithmetic was for him a half-mystical theory of number; geometry was not a measuring of the earth, it was a discipline of pure reason, a portal to the mind of God. Plutarch tells of Plato’s “indignation” at Eudoxus and Archytas for carrying on experiments in mechanics, “as the mere corruption and annihilation of the one good of geometry, which was thus shamefully turning its back upon the unembodied objects of pure intelligence to recur to sensation, and to ask help . . . from matter.” In this way, Plutarch continues, “Mechanics came to be separated from geometry, and, repudiated or neglected by philosophers, took its place as a military art.”2 Nevertheless, in his own abstract way, Plato served mathematics well. He redefined the point as the beginning of a line,3 formulated a rule for finding square numbers that are the sum of two squares,4 and invented or developed mathematical analysis5—i.e., the proof or disproof of a proposition by considering the results that follow from assuming it; the reductio ad absurdum is one form of this method. The emphasis on mathematics, in the curriculum of the Academy, helped the science if only by training such creative pupils as Eudoxus of Cnidus and Heracleides of Pontus.

  Plato’s friend Archytas, besides being seven times chosen strategos of Taras, and writing several tracts of Pythagorean philosophy, developed the mathematics of music, doubled the cube, and wrote the first known treatise on mechanics. Antiquity credited him with three epochal inventions—the pulley, the screw, and the rattle; the first two laid the foundations of machine industry, the third, says the grave Aristotle, “gave children something to occupy them, and so prevented them from breaking things about the house.”6 In this same age Dinostratus “squared the circle” by using the quadratrix curve. His brother Menaechmus, a pupil of Plato, founded the geometry of conic sections,* doubled the cube, formulated the theoretical construction of the five regular solids,† advanced the theory of irrational numbers, and gave the world a famous phrase. “O King,” he said to Alexander, “for traveling over the country there are both royal roads and roads for common citizens; but in geometry there is one road for all.”‡8

  The great name in fourth-century science is Eudoxus, who helped Praxiteles to give Cnidus a niche in history. Born there about 408, he set out at the age of twenty-three to study medicine with Philistion at Locri, geometry with Archytas at Taras, and philosophy with Plato at Athens. He was poor, and lived cheaply at the Piraeus, whence he walked to the Academy every scholastic day. After a stay in Cnidus he went to Egypt and spent sixteen months studying astronomy with the priests of Heliopolis. We find him next in Propontine Cyzicus, lecturing on mathematics. At the age of forty he moved with his pupils to Athens, opened there a school of science and philosophy, and for a time rivaled Plato. Finally he returned to Cnidus, set up an observatory, and was entrusted with the task of giving the city a new code of laws.9

  His contributions to geometry were fundamental. He invented the theory of proportion,§ and most of the propositions, transmitted to us in the fifth book of Euclid; and he devised the method of exhaustion which made it possible to calculate the area of the circle and the volume of the sphere, the pyramid, and the cone; without this preliminary work Archimedes would have been impossible. But the absorbing interest of Eudoxus was in astronomy. We catch the spirit of the scientist in his remark that he would gladly be consumed like Phaethon if he might thereby discover the nature, size, and form of the sun.10 The word astrology was then used to include what we call astronomy, but Eudoxus advised his pupils to ignore the Chaldean theory that a person’s fortune could be told by noting the position of the stars at the time of his birth. He longed to reduce all celestial motions to fixed laws; and in his Phainomena—which antiquity considered its greatest book on astronomy—he laid the foundation for the scientific predicton of the weather.

  His most famous theory was a brilliant failure. He suggested that the universe was composed of twenty-seven transparent and therefore invisible spheres, revolving in diverse directions and at various speeds about the center of the earth; and that the heavenly bodies were fixed upon the periphery or shell of these concentric spheres. The system now seems fantastic, but it was one of the first attempts to give a scientific explanation of celestial behavior. In accord with it Eudoxus calculated with considerable accuracy (if we may rashly take our present “knowledge” of these matters as a norm) the synodic and zodiacal periods of the planets.* The theory did more than any other in antiquity to stimulate astronomic research.

  Ecphantus of Syracuse wrote, about 390: “The earth moves about its own center in an eastward direction.”12 Heracleides of Pontus, one of the great polymaths of antiquity—the author of famous works on grammar, music, poetry, rhetoric, history, geometry, logic, and ethics—took up the suggestion, or advanced it independently, arguing that instead of the whole universe revolving about the earth, the relevant phenomena can be explained by supposing that the earth itself rotates daily upon its axis.13 Venus and Mercury, said Heracleides, revolve around the sun. For one brilliant moment, perhaps, Heracleides anticipated Aristarchus and Copernicus, for we read in the fragments of Geminus (ca. 70 B.C.): “Heracleides of Pontus said that, even on the assumption that the earth moves in a certain way, while the sun is in a certain way at rest, the apparent irregularity with reference to the sun can be saved.”14 We shall probably never know just what Heracleides meant.

  Meanwhile a modest progress was being made in the sciences. In geography Dicaearchus of Messana, the biographer of Greece, measured the height of mountains, established the circumference of the earth at some thirty thousand miles, and noted the influence of the sun upon the tides. In 325 Nearchus, one of Alexander’s generals, sailed from the mouth of the Indus along the southern coast of Asia to the Euphrates; his log, partly preserved in Arrian’s Indica,15 was one of the classics of ancient geography. Geodesy—the measurement of land surfaces, elevations, depressions, positions, and volumes—had already been christened (geodaisia) as distinct from geometry.16 Philistion of Italian Locri, at the beginning of the century, practiced animal dissection, and called the heart the main regulator of life, the seat of the pneuma, or soul. Diocles of Euboean Carystus, about 370, dissected the womb of animals, described human embryos of twenty-seven to forty days, advanced anatomy, embryology, gynecology, and obstetrics, and scotched a favorite Greek error by announcing that both sexes contribute “seed” to form the embryo.17 A second Aspasia became one of the famous physicians of fourth-century Athens, renowned for her work in women’s diseases, surgery, and other branches of medicine.18 And lest medical science should lower the death rate too fast for the means of subsistence, Aeneas Tacticus, the Arcadian, published about 360, in time for Philip and Alexander, the first Greek classic on the art of war.

  II. THE SOCRATIC SCHOOLS

  1. Aristippus

  If it was a middling age in science the fourth century was the heyday of philosophy. The early thinkers had propounded vague cosmologies; the Sophists had doubted everything but rhetoric; Socrates had raised a thousand questions and answered none; now all the seeds that had been planted in two hundred years sprouted into great systems of metaphysical, ethical, and political speculation. Athens, too poor to maintain its state medical service, nevertheless open
ed private universities that made it, as Isocrates said, the “school of Hellas,” the intellectual capital and arbiter of Greece. Having weakened the old religion, the philosophers struggled to find in nature and reason some substitute for it as a prop of morals and a guide to life.

  They explored first the paths opened up by Socrates. While the Sophists relapsed for the most part into the teaching of rhetoric, and disappeared as a class, the pupils of Socrates became the storm centers of violently divergent philosophies. Eucleides of Megara, who had often traveled to Athens to hear Socrates, stirred up his native city with “a rage of disputes,” as Timon of Athens phrased it,19 and developed the dialectic of Zeno and Socrates into an eristic, or art of argument, that questioned every conclusion, and led in the next century to the skepticism of Pyrrho and Carneades. After Eucleides’ death his brilliant disciple Stilpo led the Megarian school more and more towards the Cynic point of view: since every philosophy can be refuted, wisdom lies not in metaphysical speculation but in such simple living as will liberate the individual from dependence upon the external factors in well-being. When, after the sack of Megara, Demetrius Poliorcetes inquired how much Stilpo had lost, the sage replied that he had never possessed anything but knowledge, and no one had taken this away.20 In his later years he numbered among his students the founder of the Stoic philosophy, so that the Megarian school may be said to have begun with one Zeno, and ended with another.

  The elegant Aristippus, after Socrates’ death, traveled to various cities, spent some time with Xenophon at Scillus but more with Lais in Corinth,21 and then settled down to found a school of philosophy in his native Cyrene, on the coast of Africa. The wealth and luxury of the upper classes in the half-Oriental city had formed his habits, and he agreed most with that part of his master’s doctrine which called happiness the greatest good. Handsome in figure, refined in manners, clever in speech, he made a way for himself everywhere. Shipwrecked and penniless in Rhodes, he went to a gymnasium, discoursed, and so fascinated the men there that they provided him and his companions with all comforts; whereupon he remarked that parents should arm their children with such wealth that even after a shipwreck it should be able to swim to land with its owner.22

  His philosophy was simple and candid. Whatever we do, said Aristippus, is done through hope of pleasure or fear of pain—even when we impoverish ourselves for our friends, or give our lives for our generals. Therefore, by common consent, pleasure is the ultimate good, and everything else, including virtue and philosophy, must be judged according to its capacity to bring us pleasure. Our knowledge of things is uncertain; all that we know directly and surely is our feelings; wisdom, then, lies in the pursuit not of abstract truth but of pleasurable sensations. The keenest pleasures are not intellectual or moral, they are physical or sensual; therefore the wise man will seek physical delights above all. Nor will he sacrifice a present good to a conjectural future good; only the present exists, and the present is probably as good as the future, if not better; the art of life lies in plucking pleasures as they pass, and making the most of what the moment gives.23 The use of philosophy is that it may guide us not away from pleasures, but to the most pleasant choice and use of them. It is not the ascetic who abstains that is pleasure’s master, but rather the man who enjoys pleasures without being their slave, and can prudently distinguish between those that endanger him and those that do not; hence the wise man will show a discriminating respect for public opinion and the laws, but will seek as far as possible “to be neither the master nor the slave of any man.”24

  If it is a credit to a man that he practices what he preaches, Aristippus deserves some honor. He bore poverty and riches with equal grace, but made no pretense to impartiality between them. He insisted on being paid for his instructions, and did not hesitate to flatter tyrants to gain his end. He smiled patiently when Dionysius I spat upon him: “A fisherman,” he said, “must put up with more moisture than this to. catch even a smaller fish.”25 When a friend reproached him for kneeling before Dionysius he answered that it was not his fault if the King “had his ears in his feet”; and when Dionysius asked him why philosophers haunt the doors of the rich, but the rich do not frequent the presence of philosophers, he replied, “Because the first know what they want but the second do not.”26 Nevertheless he despised men who pursued wealth for its own sake. When the rich Phrygian Simus displayed to him an ornate house paved with marble, Aristippus spat in his face; and when Simus protested he excused himself on the ground that he could not find, amid all this marble, “a more suitable place to spit in.”27 Having made money, he spent it lavishly on good food, good clothing, good lodging, and (as they seemed to him) good women. Being reproved for living with a courtesan, he answered that he had no objection to living in a house, or sailing in a ship, that other men had used before him.28 When his mistress said to him, “I am in a family way by you,” he replied, “You can no more tell that it was I, than you could tell, after going through a thicket, which thorn had scratched you.”29

  People liked him despite his honest ways, for he was a person of pleasant manner, refined culture (pace Simus), and kindly heart. Doubtless his blunt hedonism was in part due to his delight in scandalizing the respectable sinners of the town. He gave himself away by reverencing Socrates, loving philosophy,* and confessing that the most impressive spectacle in life is the sight of a virtuous man steadily pursuing his course in the midst of vicious people.31 Before his death (356) he remarked that the greatest legacy he was leaving to his daughter Arete was that he had taught her “to set a value on nothing that she can do without”32—a strange surrender to Diogenes. She succeeded him as head of the Cyrenaic school, wrote forty books, had many distinguished pupils, and earned from her city an honorable epitaph—“The Light of Hellas.”33

  2. Diogenes

  Antisthenes agreed with the conclusion, but not the arguments, of this philosophy, and drew out of the same Socrates an ascetic theory of life. The founder of the Cynic school was the son of an Athenian citizen and a Thracian slave. He fought bravely at Tanagra in 426. He studied for a time with Gorgias and Prodicus, and then set up his own school; but having heard Socrates discourse, he went over—taking his pupils with him—to learn the wisdom of the older man. Like Eudoxus he lived at the Piraeus, and walked to Athens nearly every day—four or five miles each way. Perhaps he was present when Socrates (or Plato) discussed with a complaisant interlocutor the problem of pleasure.

  Socr. Do you think that the philosopher ought to care about the pleasures of . . . eating and drinking?

  Simmias. Certainly not.

  Socr. And what do you say of the pleasures of love—should he care about them?

  Sim. By no means.

  Socr. And will he think much of the other ways of indulging the body—for example, the acquisition of costly raiment, or sandals, or other adornments of the body? Instead of caring about these does he not rather despise anything beyond what nature needs?

  Sim. I should say that the true philosopher would despise them.34

  This is the essence of the Cynic philosophy: to reduce the things of the flesh to bare necessities in order that the soul may be as free as possible. Antisthenes took the doctrine literally, and became a Greek Franciscan without theology. Aristippus’ motto was, “I possess, but am not possessed”; Antisthenes’ was, “I do not possess, in order not to be possessed.” He had no property,35 and dressed in so ragged a cloak that Socrates twitted him: “I can see your vanity, Antisthenes, through the holes of your cloak.”36 Aside from this his only weakness was the writing of books, of which he left ten; one of them was a history of philosophy. After Socrates died Antisthenes resumed his role as teacher. He chose as his lecture center the gymnasium Cynosarges (Dogfish) because it was maintained for people of low, or alien, or illegitimate birth; the name Cynic became attached to the school rather from the place than from the creed.37 Antisthenes dressed like a workman, took no pay for his teaching, and preferred the poor for his pupils; anyone u
nwilling to practice poverty and hardship was driven away by Antisthenes’ tongue or his club.

  He refused at first to take Diogenes as a pupil; Diogenes insisted, bore insult patiently, was received, and made his teacher’s doctrine famous throughout Hellas by living it completely. Antisthenes had been half slave in origin; Diogenes was a bankrupt banker from Sinope. Diogenes had begged from actual want, and was pleased to learn that this was a part of virtue and wisdom. He adopted the beggar’s garb, wallet, and staff, and for a time made his home in a tub or cask in the court of the temple of Cybele at Athens.38 He envied the simple life of animals, and tried to imitate it; he slept on the ground, ate what he could find wherever he found it, and (we are assured) performed the duties of nature and the rites of love in the sight of all.39 Seeing a child drink from its hands, he threw away his cup.40 Sometimes he carried a candle or a lantern, saying that he was looking for a man.41 He injured no one, but refused to recognize laws, and announced himself, long before the Stoics, a kosmopolites, or Citizen of the World. He traveled leisurely, and we hear of him living for a time in Syracuse. On one of his journeys he was captured by pirates, who sold him as a slave to Xeniades of Corinth. When his owner asked him what he could do, he answered, “Govern men.” Xeniades made him tutor of his sons and manager of his household, in which capacities Diogenes did so well that his master called him “a good genius,” and took his advice in many things. Diogenes continued to live his simple life, so consistently that he became, next to Alexander, the most famous man in Greece.