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HANNO [
] history did not survive but undoubtedly served as an inspiration for his greater successor, Herodotus, a couple of gener ations later. Because Herodotus’ history
remains one of the greatest of all times, in sheer charm of style, if not always in accuracy), it is the later historian, who is known as the father of history, though Hecataeus may better deserve the title. Like Thales, Hecataeus was a shrewd politician, and he opposed the revolt of the Greek cities of Asia Minor against Darius I of Persia in 499 B.C. His advice was not followed, the revolt was disas trously suppressed, and the scientific pre-eminence of the Greek cities of Asia Minor, which had lasted a century and a half, came to an end. [10] HERACLITUS (her-uh-kly'tus) Greek philosopher
north
o f Miletus), about 540 b .
. Died: about 475 B.c. The work of Heraclitus survives only in fragments. His pessimistic view of life and the universe led to his being called the “weeping philosopher.” To him the most permanent thing about the universe seemed to be impermanence, and the one fact that was unchangeable was that change was certain. For instance, he thought so little of the unchangeability of even so glorious an object as the sun, as to suggest it was made fresh each morning so that every day saw a dif ferent sun. It made sense to him, then, that fire, itself ever-changing and capable of bringing about change in other things, should be the fundamental element of the universe. [11] ALCMAEON (alk-mee'on) Greek physician
about 535 b .
. Died: date unknown Alcmaeon, bom in the center of Py- thagoreanism and living during the height of its power, was naturally a Pythag orean. He had some mystical notions, such as that the human body was a microcosm, reflecting in small the uni verse or macrocosm. This, however, did not prevent him from being an accurate and careful observer. He is the first individual known to have conducted dissections of the human body. He recorded the existence of the optic nerve and the tube connecting the ear and mouth (which are now called Eustachian tubes after Eustachio [141], their rediscoverer, who lived two thou sand years later). Alcmaeon distin guished arteries from veins, though he did not recognize the former as blood vessels, since in cadavers the arteries are empty.
He felt that the brain was the center of intellectual activity and so did Democ ritus [20] and Hippocrates [22] two generations later. This view, however, was not accepted by Aristotle [29] and it did not come into its own until modern times. [12] HANNO Carthaginian navigator Born: Carthage (near the site of modern Tunis), about 530 b .
. Died: date unknown The Phoenicians (of whom the Car thaginians were a branch) were the great navigators and explorers of the ancient world but only a dim tale of Hanno, with sixty vessels and thirty thousand men and women (numbers undoubtedly exaggerated) and his explorations down the African coast survives. Herodotus, the Greek historian, describes the voyage and declares that Hanno claimed to have circumnavigated Africa. Concerning this, Herodotus expresses his doubts, because the Carthaginians reported that in the far south the noonday sun was in the northern half of the sky. This Herodotus felt to be impossible. Nevertheless, this is the case in the southern hemisphere and it is unlikely that anyone would make up so ridiculous a tale unless he had actu ally witnessed the phenomenon. Thus, the very point at which the ordinarily 7 [13] PARMENIDES ANAXAGORAS [14] credulous Herodotus balks is the point that is most convincing to moderns. It may be, then, that Hanno the Carthagin ian was the first man of the Mediter ranean world to have crossed the equa tor.
Greek philosopher Bom: Elia (modem Velia), Italy, about 515 b .
. Died: afte r
450 b . c . Parmenides was a follower of those notable Ionian exiles Pythagoras [7] and Xenophanes [6] and was the first major philosopher native to Italy. He opposed the notions of Heraclitus [10] and, far from accepting change as the universal truth, denied the possibility of change since one object, he held, could not turn into another object fundamentally different. It was more reasonable, he insisted, to suppose that creation (some thing from nothing) and destruction (nothing from something) were impossi ble. Since change was all about us despite this reasoning, Parmenides had to choose between the senses and reason; he chose reason. The senses were untrustworthy, in his opinion, and not to be used as guides. This view was the cornerstone of the Eleatic school, which he founded and of which the best-known member, Zeno [16], was to carry the distrust of the senses into a set of famous paradoxes. Plato [24] entitled one of his dialogues “Parmenides” and in it describes a meet ing between the aged Parmenides and the youthful Socrates [21].
Greek philosopher Born: Clazomenae (75 miles north
of Miletus), about 500 b .
. Died: Lampsacus (modern Lâp- seki, Turkey), about 428 b .
. As is the case for almost all the early Greek philosophers, tradition states that Anaxagoras, the son of wealthy parents, traveled widely during his youth. He is sometimes said to have studied under Anaximenes [5] but this is probably in order to maintain an Ionian continuity. Anaximenes is almost sure to have been dead before Anaxagoras was old enough to be a student. About 462 b .
., Anaxagoras migrated to Athens from his Asia Minor home land. Athens at the time was at the height of its golden age and the pinnacle of Greek culture. By his move Anax agoras, the last of the Ionians, carried to Athens the scientific tradition of Thales [3] as, two generations earlier, Pythag oras [7] had carried it to Italy. How ever, whereas Pythagoras had empha sized mysticism, Anaxagoras was a ra tionalist. He explained—accurately—the phases of the moon and eclipses of both moon and sun in terms of the move ments of those bodies. To him the universe originated not through the creative act of any deity, but through the action of abstract Mind upon an infinite number of “seeds.” These seeds were a form of the atoms whose existence was being postulated si multaneously by Leucippus [15]. The result, according to Anaxagoras, was that the heavenly bodies were brought into existence by the same processes that formed the earth, and therefore heavens and earth were com posed of the same materials. The exis tence of a stony meteorite that fell on the north shore of the Aegean in 468 b . c . may have helped him come to this conclusion. The stars and planets were flaming rocks, and the sun he believed to be an incandescent rock about the size of the Peloponnesus (which is roughly as large as Massachusetts). As for the moon, he regarded it as an earthlike body and possibly even inhabited. These were irreligious views that shocked con servative Athenians. Anaxagoras taught in Athens for thirty years and his school was the beginning of the philosophic pre-eminence of Athens in the Greek world, a pre eminence that was to be maintained for nearly a thousand years. (Even in late Roman times, when Athens’ early mili tary and political glory was a faded and ancient dream, it kept the scholarly aura 8 [15] LEUCIPPUS ZENO [
] of the University town, much as Oxford does today in England.) He is supposed to have written one book, some time after 467 b . c . Anaxagoras was not, however, allowed to pursue his studies and teachings in peace. The Athens of his day was not yet ready to accept his rationalism (as the Greeks of Italy had not been ready to accept Pythagoras’ aristocratic mys ticism). Anaxagoras was accused of im piety and atheism and brought to trial, the first scientist we know to have had this kind of legal conflict with a state religion. Anaxagoras was a friend of the most respected Athenian citizens, includ ing Euripides, the great playwright, and even Pericles, the uncrowned king of the city. This hurt rather than helped Anax agoras, for the enemies of Pericles, un able to strike at the leader himself, ea gerly attempted to hurt him through his friend the philosopher. Pericles faced the court in his friend’s defense and man aged, with difficulty, to secure his acquit tal of the charge of impiety (a happier fate than was to befall Socrates [21] on a similar charge a generation later). Anaxagoras believed the atmosphere of the city to be unsafe, however, and in 434
b . c . he retired to Lampsacus on the Hellespont, where he died six years later. The mark of the trial endured. To be sure, a younger contemporary, Meton [23], continued astronomical researches at Athens, but the city’s thinkers turned away from natural philosophy to take up moral philosophy. [15] LEUCIPPUS (lyoo-sip'us) Greek philosopher
B.C.
Died: date unknown Almost nothing is known of Leu cippus, not even that he really lived. If he did, he represented the final flash of the old tradition of Asia Minor, some how surviving the destruction of the coastal cities by Persia. He is supposed to have been a pupil of Zeno [16]. He was, apparently, the inventor of atomism, the teacher of Democritus [20], and the first to state the rule of causality, that is, that every event has a natural cause.
Greek philosopher Born: Elea (modem Velia), southern Italy, about 490 b .
. Died: Elea, about 425 b . c . Zeno is the chief of the Eleatic school of philosophy (the name being taken from the town of Elea, where it was cen tered). He may have been a student of Parmenides [13], He appears to have lived in Athens for a time according to Plato [24] and is supposed to have taught Pericles, among others. His life ended, according to one account, when he was on the wrong side of a political argument and was executed for treason. The Eleatic school denied the use fulness of the senses as a means of at taining truth. In fact the Eleatics at tempted to demonstrate that by reason they could show that the message of the senses must be ignored. Zeno presented the Greek thinkers with four famous paradoxes, all of which seemed to disprove the possibility of mo tion as it was sensed. Tlie best known is that of Achilles and the tortoise. Suppose Achilles can ran ten times as fast as a tortoise and the tortoise has a ten-yard head start. It follows then that Achilles can never overtake the tortoise because while he covers the ten yards’ difference, the tortoise will have moved ahead one yard. When Achilles covers that one yard, the tortoise will have moved on a tenth of a yard and so on. Since our senses, however, clearly show us a fast runner overtaking and passing a slow runner, our senses must be false. These paradoxes, although all based on fallacies, were of the utmost impor tance to science, for they stimulated thought. Aristotle [29], for instance, pre sented arguments against them, and down to our own day, others have taken up positions either for or against the Eleatic view. Since Zeno’s paradoxes were all based on the assumption that space and time are infinitely divisible, it encouraged men 9 [17] EMPEDOCLES EMPEDOCLES [17] like Democritus [20] to avoid the para doxes by searching for indivisibility and finding it in the atoms of which they claimed matter to be composed. This view did not win general favor in Greek times, but it did win out twenty-two cen turies later with Dalton [389]. The no tion of infinite divisibility was further erased, a hundred years after Dalton, by the theories of Planck [887] concerning the ultimate particles of energy. In pure mathematics, it was shown al most twenty-one centuries later, by James Gregory [226], that such things as converging series existed, in which an infinite number of terms nevertheless added up to a finite sum. The Achilles- and-the-tortoise paradox involved (with out Zeno’s knowledge) such a converg ing series. Then, too, methods for han dling the infinitely divisible (even were that supposed to exist) were not devel oped until Newton [231] and his inven tion of the calculus. Zeno was completely defeated in the end, but he deserves a chorus of thanks just the same for the values that grew out of more than two millennia of intel lectual struggle required to defeat him. (Zeno of Elea is sometimes confused with another Zeno, Zeno of Citium, who founded the Stoic school of philosophy almost two centuries after the time of the earlier Zeno.)
Greek philosopher Born: Akragas (modern Agri- gento), Sicily, about 492 b .
. Died: Mount Etna (?), about 432 B.C.
Empedocles was one philosopher who, at least in younger life, did not hesitate to immerse himself in politics. He was a moving spirit in the overthrow of a tyr anny in his native town of Akragas. The grateful citizens offered him the tyrant’s seat in reward but, in a self-denial not often found among Greeks of the time, Empedocles refused. He preferred to spend his time on philosophy. Empedocles was, to a considerable ex tent, under the influence of the teachings of Pythagoras [7], This is shown in the strong vein of mysticism in his teachings. He had no objection to being looked upon as a prophet and miracle-worker and was even supposed to have brought dead people back to life. According to one tradition, he let it be known that on a particular day he would be taken up to heaven and made a god. On that day he is supposed to have jumped into the cra ter of Mount Etna in order that, by disappearing mysteriously, he might be thought to have made good on his pre diction. (It is also possible he believed his own story and jumped into the crater in despair when the heavenly chariot failed to appear. It is even more possible the whole story is false, for there are some who say he traveled to Greece in later life and died there.) Some of Empedocles’ views were ratio nal enough. He believed the moon shone by reflected light from the sun. He believed the heart was the center of the blood-vessel system (which is true) and therefore the seat of life (which is cer tainly not an unreasonable guess). This notion was passed on to Aristotle [29], from whom it has descended to our day. We still speak of “not having the heart to do it” when we mean not having the will. We say we are “lion-hearted” when we mean brave, “broken-hearted” when we mean disappointed, and so on. He also had a dim notion of an evolutionary process through natural selection and felt that some creatures, ill-adapted to life, had perished in the past. This was a foretaste of Darwin [554]. Another influential notion arose when Empedocles combined some of the views of the Asia Minor school. Where Thales [3] had thought the basic element of the universe was water, Anaximenes [5] air, Heraclitus [10] fire, and Xenophanes [6] earth, Empedocles hit on merging all these. All things, he believed, were made up of various combinations and arrange ments of these. Substances changed in nature when the elements broke apart and recombined in new arrangements under the action of forces akin to what humans recognize as “love” and “strife.” The notion was taken up and im proved by Aristotle and remained the
[18] OENOPIDES DEMOCRITUS [
] basis of chemical theory for more than two thousand years. It lasts in the com mon language even today, for we speak of the “raging of the elements” when we mean that air and water are being lashed into fury by a storm. [18] OENOPIDES (ee-nop'ih-deez) Greek philosopher
ab o ut
480 b . c .
Nothing is known about Oenopides ex cept for mentions in the surviving works of other Greeks. Pythagoras [7] probably knew that the path marked out by the sun was at an angle to the celestial equator, something called the obliquity of the ecliptic. In modem terms, this means that earth’s axis of rotation is at an angle to a line perpendicular to its plane of revolution about the sun. The Babylonians knew this before Pythagoras. It may be, though, that Oenopides was the first actually to put a figure to the amount of tipping, and that he placed it at about 24°, which is only a half-degree greater than the true value. He may also have fixed the length of the year at 365% days, which is a trifle longer than the actual length, which is nearly 365%. [19] PHILOLAUS (fil-oh-lay'us) Greek philosopher
southern Italy), about 480 b .
. Died: date unknown Philolaus was the most eminent (after Pythagoras [7] himself) of the Pythag orean school and was the first, ap parently, to publish Pythagorean views for the general public. He suffered in the course of the persecutions to which the Pythagoreans were subjected in southern Italy and had to flee (at least tempo rarily) to Thebes, on the Greek main land. Later he returned to Tarentum, the last stronghold of Pythagoreanism. The majority of the contributions of Philolaus were highly mystical. One thought, however, was of particular in terest, for within the Pythagorean non sense there were occasional shrewd (or lucky) guesses, as was the case with Xenophanes [6]. In Philolaus’ case the shrewd guess was that the earth was not the center of the universe but that it moved through space. The earth, he thought, along with the sun, moon, Mercury, Venus, Mars, Jupiter, Saturn, and the stars circled in separate spheres about a central fire, of which the visible sun was only a reflec tion.
This meant nine circling spheres, so Philolaus invented a tenth, occupied by a counter-earth, a planet always hidden from us on the other side of the sun. This whole scheme was designed merely to take advantage of the magical powers of the number 10 (magical because it was the sum of 1, 2, 3, and 4). Whatever the motivation, however, this was the first known speculation that the earth moves through space. When, two thousand years later, Copernicus [127] was to advance his theory of the universe, in which the earth and planets were pictured as moving about the sun, it was branded by some of his opponents a Pythagorean heresy. [20] DEMOCRITUS (de-mok'rih-tus) Greek philosopher
B.C.
Died: perhaps as late as 380 b . c . Like Thales [3] and Pythagoras [7] be fore him, Democritus is supposed to have traveled widely in Egypt and the East before settling down to philosophy at home in Greece. He also picked up the rationalist world view of Asia Minor through his teacher, Leucippus [15], who was of Miletus, as Thales himself had been. Like all the early rationalists, he had some startlingly modem-sounding notions. He maintained, for instance, that the Milky Way was a vast conglom eration of tiny stars and that the moon was an earthlike world with mountains and valleys. Download 17.33 Mb. Do'stlaringiz bilan baham: 
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