A History of Science Volume I Part 5

His, indeed, would seem to have been a mind in which practical common-sense was strangely blended with the capacity for wide and imaginative generalization. As further evidence of his practicality, it is a.s.serted that he was the first person who introduced measures and weights among the Greeks, this a.s.sertion being made on the authority of Aristoxenus. It will be observed that he is said to have introduced, not to have invented, weights and measures, a statement which suggests a knowledge on the part of the Greeks that weights and measures were previously employed in Egypt and Babylonia.

The mind that could conceive the world as a sphere and that interested itself in weights and measures was, obviously, a mind of the visualizing type. It is characteristic of this type of mind to be interested in the tangibilities of geometry, hence it is not surprising to be told that Pythagoras "carried that science to perfection." The most famous discovery of Pythagoras in this field was that the square of the hypotenuse of a right-angled triangle is equal to the squares of the other sides of the triangle. We have already noted the fable that his enthusiasm over this discovery led him to sacrifice a hecatomb.

Doubtless the story is apocryphal, but doubtless, also, it expresses the truth as to the fervid joy with which the philosopher must have contemplated the results of his creative imagination.

No line alleged to have been written by Pythagoras has come down to us.

We are told that he refrained from publishing his doctrines, except by word of mouth. "The Lucanians and the Peucetians, and the Messapians and the Romans," we are a.s.sured, "flocked around him, coming with eagerness to hear his discourses; no fewer than six hundred came to him every night; and if any one of them had ever been permitted to see the master, they wrote of it to their friends as if they had gained some great advantage." Nevertheless, we are a.s.sured that until the time of Philolaus no doctrines of Pythagoras were ever published, to which statement it is added that "when the three celebrated books were published, Plato wrote to have them purchased for him for a hundred minas."(2) But if such books existed, they are lost to the modern world, and we are obliged to accept the a.s.sertions of relatively late writers as to the theories of the great Crotonian.

Perhaps we cannot do better than quote at length from an important summary of the remaining doctrines of Pythagoras, which Diogenes himself quoted from the work of a predecessor.(3) Despite its somewhat inchoate character, this summary is a most remarkable one, as a brief a.n.a.lysis of its contents will show. It should be explained that Alexander (whose work is now lost) is said to have found these dogmas set down in the commentaries of Pythagoras. If this a.s.sertion be accepted, we are brought one step nearer the philosopher himself. The summary is as follows:

"That the monad was the beginning of everything. From the monad proceeds an indefinite duad, which is subordinate to the monad as to its cause.

That from the monad and the indefinite duad proceed numbers. And from numbers signs. And from these last, lines of which plane figures consist. And from plane figures are derived solid bodies. And from solid bodies sensible bodies, of which last there are four elements--fire, water, earth, and air. And that the world, which is indued with life and intellect, and which is of a spherical figure, having the earth, which is also spherical, and inhabited all over in its centre,(4) results from a combination of these elements, and derives its motion from them; and also that there are antipodes, and that what is below, as respects us, is above in respect of them.

"He also taught that light and darkness, and cold and heat, and dryness and moisture, were equally divided in the world; and that while heat was predominant it was summer; while cold had the mastery, it was winter; when dryness prevailed, it was spring; and when moisture preponderated, winter. And while all these qualities were on a level, then was the loveliest season of the year; of which the flourishing spring was the wholesome period, and the season of autumn the most pernicious one. Of the day, he said that the flourishing period was the morning, and the fading one the evening; on which account that also was the least healthy time.

"Another of his theories was that the air around the earth was immovable and pregnant with disease, and that everything in it was mortal; but that the upper air was in perpetual motion, and pure and salubrious, and that everything in that was immortal, and on that account divine. And that the sun and the moon and the stars were all G.o.ds; for in them the warm principle predominates which is the cause of life. And that the moon derives its light from the sun. And that there is a relationship between men and the G.o.ds, because men partake of the divine principle; on which account, also, G.o.d exercises his providence for our advantage.

Also, that Fate is the cause of the arrangement of the world both generally and particularly. Moreover, that a ray from the sun penetrated both the cold aether and the dense aether; and they call the air the cold aether, and the sea and moisture they call the dense aether. And this ray descends into the depths, and in this way vivifies everything.

And everything which partakes of the principle of heat lives, on which account, also, plants are animated beings; but that all living things have not necessarily souls. And that the soul is a something tom off from the aether, both warm and cold, from its partaking of the cold aether. And that the soul is something different from life. Also, that it is immortal, because that from which it has been detached is immortal.

"Also, that animals are born from one another by seeds, and that it is impossible for there to be any spontaneous production by the earth.

And that seed is a drop from the brain which contains in itself a warm vapor; and that when this is applied to the womb it transmits virtue and moisture and blood from the brain, from which flesh and sinews and bones and hair and the whole body are produced. And from the vapor is produced the soul, and also sensation. And that the infant first becomes a solid body at the end of forty days; but, according to the principles of harmony, it is not perfect till seven, or perhaps nine, or at most ten months, and then it is brought forth. And that it contains in itself all the principles of life, which are all connected together, and by their union and combination form a harmonious whole, each of them developing itself at the appointed time.

"The senses in general, and especially the sight, are a vapor of excessive warmth, and on this account a man is said to see through air and through water. For the hot principle is opposed by the cold one; since, if the vapor in the eyes were cold, it would have the same temperature as the air, and so would be dissipated. As it is, in some pa.s.sages he calls the eyes the gates of the sun; and he speaks in a similar manner of hearing and of the other senses.

"He also says that the soul of man is divided into three parts: into intuition and reason and mind, and that the first and last divisions are found also in other animals, but that the middle one, reason, is only found in man. And that the chief abode of the soul is in those parts of the body which are between the heart and the brain. And that that portion of it which is in the heart is the mind; but that deliberation and reason reside in the brain.

"Moreover, that the senses are drops from them; and that the reasoning sense is immortal, but the others are mortal. And that the soul is nourished by the blood; and that reasons are the winds of the soul.

That it is invisible, and so are its reasons, since the aether itself is invisible. That the links of the soul are the veins and the arteries and the nerves. But that when it is vigorous, and is by itself in a quiescent state, then its links are words and actions. That when it is cast forth upon the earth it wanders about, resembling the body.

Moreover, that Mercury is the steward of the souls, and that on this account he has the name of Conductor, and Commercial, and Infernal, since it is he who conducts the souls from their bodies, and from earth and sea; and that he conducts the pure souls to the highest region, and that he does not allow the impure ones to approach them, nor to come near one another, but commits them to be bound in indissoluble fetters by the Furies. The Pythagoreans also a.s.sert that the whole air is full of souls, and that these are those which are accounted daemons and heroes. Also, that it is by them that dreams are sent among men, and also the tokens of disease and health; these last, too, being sent not only to men, but to sheep also, and other cattle. Also that it is they who are concerned with purifications and expiations and all kinds of divination and oracular predictions, and things of that kind."(5)

A brief consideration of this summary of the doctrines of Pythagoras will show that it at least outlines a most extraordinary variety of scientific ideas. (1) There is suggested a theory of monads and the conception of the development from simple to more complex bodies, pa.s.sing through the stages of lines, plain figures, and solids to sensible bodies. (2) The doctrine of the four elements--fire, water, earth, and air--as the basis of all organisms is put forward. (3) The idea, not merely of the sphericity of the earth, but an explicit conception of the antipodes, is expressed. (4) A conception of the sanitary influence of the air is clearly expressed. (5) An idea of the problems of generation and heredity is shown, together with a distinct disavowal of the doctrine of spontaneous generation--a doctrine which, it may be added, remained in vogue, nevertheless, for some twenty-four hundred years after the time of Pythagoras. (6) A remarkable a.n.a.lysis of mind is made, and a distinction between animal minds and the human mind is based on this a.n.a.lysis. The physiological doctrine that the heart is the organ of one department of mind is offset by the clear statement that the remaining factors of mind reside in the brain. This early recognition of brain as the organ of mind must not be forgotten in our later studies. It should be recalled, however, that a Crotonian physician, Alemaean, a younger contemporary of Pythagoras, is also credited with the same theory. (7) A knowledge of anatomy is at least vaguely foreshadowed in the a.s.sertion that veins, arteries, and nerves are the links of the soul. In this connection it should be recalled that Pythagoras was a practical physician.

As against these scientific doctrines, however, some of them being at least remarkable guesses at the truth, attention must be called to the concluding paragraph of our quotation, in which the old familiar daemonology is outlined, quite after the Oriental fashion. We shall have occasion to say more as to this phase of the subject later on. Meantime, before leaving Pythagoras, let us note that his practical studies of humanity led him to a.s.sert the doctrine that "the property of friends is common, and that friendship is equality." His disciples, we are told, used to put all their possessions together in one store and use them in common. Here, then, seemingly, is the doctrine of communism put to the test of experiment at this early day. If it seem that reference to this carries us beyond the bounds of science, it may be replied that questions such as this will not lie beyond the bounds of the science of the near future.

XENOPHANES AND PARMENIDES

There is a whimsical tale about Pythagoras, according to which the philosopher was wont to declare that in an earlier state he had visited Hades, and had there seen Homer and Hesiod tortured because of the absurd things they had said about the G.o.ds. Apocrypbal or otherwise, the tale suggests that Pythagoras was an agnostic as regards the current Greek religion of his time. The same thing is perhaps true of most of the great thinkers of this earliest period. But one among them was remembered in later times as having had a peculiar aversion to the anthropomorphic conceptions of his fellows. This was Xenophanes, who was born at Colophon probably about the year 580 B.C., and who, after a life of wandering, settled finally in Italy and became the founder of the so-called Eleatic School.

A few fragments of the philosophical poem in which Xenophanes expressed his views have come down to us, and these fragments include a tolerably definite avowal of his faith. "G.o.d is one supreme among G.o.ds and men, and not like mortals in body or in mind," says Xenophanes. Again he a.s.serts that "mortals suppose that the G.o.ds are born (as they themselves are), that they wear man's clothing and have human voice and body; but,"

he continues, "if cattle or lions had hands so as to paint with their hands and produce works of art as men do, they would paint their G.o.ds and give them bodies in form like their own--horses like horses, cattle like cattle." Elsewhere he says, with great ac.u.men: "There has not been a man, nor will there be, who knows distinctly what I say about the G.o.ds or in regard to all things. For even if one chance for the most part to say what is true, still he would not know; but every one thinks that he knows."(6)

In the same spirit Xenophanes speaks of the battles of t.i.tans, of giants, and of centaurs as "fictions of former ages." All this tells of the questioning spirit which distinguishes the scientific investigator.

Precisely whither this spirit led him we do not know, but the writers of a later time have preserved a tradition regarding a belief of Xenophanes that perhaps ent.i.tles him to be considered the father of geology. Thus Hippolytus records that Xenophanes studied the fossils to be found in quarries, and drew from their observation remarkable conclusions. His words are as follows: "Xenophanes believes that once the earth was mingled with the sea, but in the course of time it became freed from moisture; and his proofs are such as these: that sh.e.l.ls are found in the midst of the land and among the mountains, that in the quarries of Syracuse the imprints of a fish and of seals had been found, and in Paros the imprint of an anchovy at some depth in the stone, and in Melite shallow impressions of all sorts of sea products. He says that these imprints were made when everything long ago was covered with mud, and then the imprint dried in the mud. Further, he says that all men will be destroyed when the earth sinks into the sea and becomes mud, and that the race will begin anew from the beginning; and this transformation takes place for all worlds."(7) Here, then, we see this earliest of paleontologists studying the fossil-bearing strata of the earth, and drawing from his observations a marvellously scientific induction. Almost two thousand years later another famous citizen of Italy, Leonardo da Vinci, was independently to think out similar conclusions from like observations. But not until the nineteenth century of our era, some twenty-four hundred years after the time of Xenophanes, was the old Greek's doctrine to be accepted by the scientific world.

The ideas of Xenophanes were known to his contemporaries and, as we see, quoted for a few centuries by his successors, then they were ignored or quite forgotten; and if any philosopher of an ensuing age before the time of Leonardo championed a like rational explanation of the fossils, we have no record of the fact. The geological doctrine of Xenophanes, then, must be listed among those remarkable Greek antic.i.p.ations of nineteenth-century science which suffered almost total eclipse in the intervening centuries.

Among the pupils of Xenophanes was Parmenides, the thinker who was destined to carry on the work of his master along the same scientific lines, though at the same time mingling his scientific conceptions with the mysticism of the poet. We have already had occasion to mention that Parmenides championed the idea that the earth is round; noting also that doubts exist as to whether he or Pythagoras originated this doctrine.

No explicit answer to this question can possibly be hoped for. It seems clear, however, that for a long time the Italic School, to which both these philosophers belonged, had a monopoly of the belief in question.

Parmenides, like Pythagoras, is credited with having believed in the motion of the earth, though the evidence furnished by the writings of the philosopher himself is not as demonstrative as one could wish.

Unfortunately, the copyists of a later age were more concerned with metaphysical speculations than with more tangible things. But as far as the fragmentary references to the ideas of Parmenides may be accepted, they do not support the idea of the earth's motion. Indeed, Parmenides is made to say explicitly, in preserved fragments, that "the world is immovable, limited, and spheroidal in form."(8)

Nevertheless, some modern interpreters have found an opposite meaning in Parmenides. Thus Ritter interprets him as supposing "that the earth is in the centre spherical, and maintained in rotary motion by its equiponderance; around it lie certain rings, the highest composed of the rare element fire, the next lower a compound of light and darkness, and lowest of all one wholly of night, which probably indicated to his mind the surface of the earth, the centre of which again he probably considered to be fire."(9) But this, like too many interpretations of ancient thought, appears to read into the fragments ideas which the words themselves do not warrant. There seems no reason to doubt, however, that Parmenides actually held the doctrine of the earth's sphericity. Another glimpse of his astronomical doctrines is furnished us by a fragment which tells us that he conceived the morning and the evening stars to be the same, a doctrine which, as we have seen, was ascribed also to Pythagoras. Indeed, we may repeat that it is quite impossible to distinguish between the astronomical doctrines of these two philosophers.

The poem of Parmenides in which the cosmogonic speculations occur treats also of the origin of man. The author seems to have had a clear conception that intelligence depends on bodily organism, and that the more elaborately developed the organism the higher the intelligence.

But in the interpretation of this thought we are hampered by the characteristic vagueness of expression, which may best be evidenced by putting before the reader two English translations of the same stanza.

Here is Ritter's rendering, as made into English by his translator, Morrison:

"For exactly as each has the state of his limbs many-jointed, So invariably stands it with men in their mind and their reason; For the system of limbs is that which thinketh in mankind Alike in all and in each: for thought is the fulness."(10)

The same stanza is given thus by George Henry Lewes:

"Such as to each man is the nature of his many-jointed limbs, Such also is the intelligence of each man; for it is The nature of limbs (organization) which thinketh in men, Both in one and in all; for the highest degree of organization gives the highest degree of thought."(11)

Here it will be observed that there is virtual agreement between the translators except as to the last clause, but that clause is most essential. The Greek phrase is (gr to gar pleon esti nohma). Ritter, it will be observed, renders this, "for thought is the fulness." Lewes paraphrases it, "for the highest degree of organization gives the highest degree of thought." The difference is intentional, since Lewes himself criticises the translation of Ritter. Ritter's translation is certainly the more literal, but the fact that such diversity is possible suggests one of the chief elements of uncertainty that hamper our interpretation of the thought of antiquity. Unfortunately, the mind of the commentator has usually been directed towards such subtleties, rather than towards the expression of precise knowledge. Hence it is that the philosophers of Greece are usually thought of as mere dreamers, and that their true status as scientific discoverers is so often overlooked. With these intangibilities we have no present concern beyond this bare mention; for us it suffices to gain as clear an idea as we may of the really scientific conceptions of these thinkers, leaving the subtleties of their deductive reasoning for the most part untouched.

EMPEDOCLES

The latest of the important pre-Socratic philosophers of the Italic school was Empedocles, who was born about 494 B.C. and lived to the age of sixty. These dates make Empedocles strictly contemporary with Anaxagoras, a fact which we shall do well to bear in mind when we come to consider the latter's philosophy in the succeeding chapter. Like Pythagoras, Empedocles is an imposing figure. Indeed, there is much of similarity between the personalities, as between the doctrines, of the two men. Empedocles, like Pythagoras, was a physician; like him also he was the founder of a cult. As statesman, prophet, physicist, physician, reformer, and poet he showed a versatility that, coupled with profundity, marks the highest genius. In point of versatility we shall perhaps hardly find his equal at a later day--unless, indeed, an exception be made of Eratosthenes. The myths that have grown about the name of Empedocles show that he was a remarkable personality. He is said to have been an awe-inspiring figure, clothing himself in Oriental splendor and moving among mankind as a superior being. Tradition has it that he threw himself into the crater of a volcano that his otherwise unexplained disappearance might lead his disciples to believe that he had been miraculously translated; but tradition goes on to say that one of the brazen slippers of the philosopher was thrown up by the volcano, thus revealing his subterfuge. Another tradition of far more credible aspect a.s.serts that Empedocles retreated from Italy, returning to the home of his fathers in Peloponnesus to die there obscurely. It seems odd that the facts regarding the death of so great a man, at so comparatively late a period, should be obscure; but this, perhaps, is in keeping with the personality of the man himself. His disciples would hesitate to ascribe a merely natural death to so inspired a prophet.

Empedocles appears to have been at once an observer and a dreamer. He is credited with noting that the pressure of air will sustain the weight of water in an inverted tube; with divining, without the possibility of proof, that light has actual motion in s.p.a.ce; and with a.s.serting that centrifugal motion must keep the heavens from falling. He is credited with a great sanitary feat in the draining of a marsh, and his knowledge of medicine was held to be supernatural. Fortunately, some fragments of the writings of Empedocles have come down to us, enabling us to judge at first hand as to part of his doctrines; while still more is known through the references made to him by Plato, Aristotle, and other commentators. Empedocles was a poet whose verses stood the test of criticism. In this regard he is in a like position with Parmenides; but in neither case are the preserved fragments sufficient to enable us fully to estimate their author's scientific attainments. Philosophical writings are obscure enough at the best, and they perforce become doubly so when expressed in verse. Yet there are certain pa.s.sages of Empedocles that are unequivocal and full of interest. Perhaps the most important conception which the works of Empedocles reveal to us is the denial of anthropomorphism as applied to deity. We have seen how early the anthropomorphic conception was developed and how closely it was all along clung to; to shake the mind free from it then was a remarkable feat, in accomplishing which Empedocles took a long step in the direction of rationalism. His conception is paralleled by that of another physician, Alcmaeon, of Proton, who contended that man's ideas of the G.o.ds amounted to mere suppositions at the very most.

A rationalistic or sceptical tendency has been the accompaniment of medical training in all ages.

The words in which Empedocles expresses his conception of deity have been preserved and are well worth quoting: "It is not impossible," he says, "to draw near (to G.o.d) even with the eyes or to take hold of him with our hands, which in truth is the best highway of persuasion in the mind of man; for he has no human head fitted to a body, nor do two shoots branch out from the trunk, nor has he feet, nor swift legs, nor hairy parts, but he is sacred and ineffable mind alone, darting through the whole world with swift thoughts."(8)

How far Empedocles carried his denial of anthropomorphism is ill.u.s.trated by a reference of Aristotle, who a.s.serts "that Empedocles regards G.o.d as most lacking in the power of perception; for he alone does not know one of the elements, Strife (hence), of perishable things." It is difficult to avoid the feeling that Empedocles here approaches the modern philosophical conception that G.o.d, however postulated as immutable, must also be postulated as unconscious, since intelligence, as we know it, is dependent upon the trans.m.u.tations of matter. But to urge this thought would be to yield to that philosophizing tendency which has been the bane of interpretation as applied to the ancient thinkers.

Considering for a moment the more tangible accomplishments of Empedocles, we find it alleged that one of his "miracles" consisted of the preservation of a dead body without putrefaction for some weeks after death. We may a.s.sume from this that he had gained in some way a knowledge of embalming. As he was notoriously fond of experiment, and as the body in question (a.s.suming for the moment the authenticity of the legend) must have been preserved without disfigurement, it is conceivable even that he had hit upon the idea of injecting the arteries. This, of course, is pure conjecture; yet it finds a certain warrant, both in the fact that the words of Pythagoras lead us to believe that the arteries were known and studied, and in the fact that Empedocles' own words reveal him also as a student of the vascular system. Thus Plutarch cites Empedocles as believing "that the ruling part is not in the head or in the breast, but in the blood; wherefore in whatever part of the body the more of this is spread in that part men excel."(13) And Empedocles' own words, as preserved by Stobaeus, a.s.sert "(the heart) lies in seas of blood which dart in opposite directions, and there most of all intelligence centres for men; for blood about the heart is intelligence in the case of man." All this implies a really remarkable appreciation of the dependence of vital activities upon the blood.

This correct physiological conception, however, was by no means the most remarkable of the ideas to which Empedoeles was led by his anatomical studies. His greatest accomplishment was to have conceived and clearly expressed an idea which the modern evolutionist connotes when he speaks of h.o.m.ologous parts--an idea which found a famous modern expositor in Goethe, as we shall see when we come to deal with eighteenth-century science. Empedocles expresses the idea in these words: "Hair, and leaves, and thick feathers of birds, are the same thing in origin, and reptile scales too on strong limbs. But on hedgehogs sharp-pointed hair bristles on their backs."(14) That the idea of trans.m.u.tation of parts, as well as of mere h.o.m.ology, was in mind is evidenced by a very remarkable sentence in which Aristotle a.s.serts, "Empedocles says that fingernails rise from sinew from hardening." Nor is this quite all, for surely we find the germ of the Lamarckian conception of evolution through the transmission of acquired characters in the a.s.sertion that "many characteristics appear in animals because it happened to be thus in their birth, as that they have such a spine because they happen to be descended from one that bent itself backward."(15) Aristotle, in quoting this remark, a.s.serts, with the dogmatism which characterizes the philosophical commentators of every age, that "Empedocles is wrong," in making this a.s.sertion; but Lamarck, who lived twenty-three hundred years after Empedocles, is famous in the history of the doctrine of evolution for elaborating this very idea.

It is fair to add, however, that the dreamings of Empedocles regarding the origin of living organisms led him to some conceptions that were much less luminous. On occasion, Empedocles the poet got the better of Empedocles the scientist, and we are presented with a conception of creation as grotesque as that which delighted the readers of Paradise Lost at a later day. Empedocles a.s.sures us that "many heads grow up without necks, and arms were wandering about, necks bereft of shoulders, and eyes roamed about alone with no foreheads."(16) This chaotic condition, so the poet dreamed, led to the union of many incongruous parts, producing "creatures with double faces, offspring of oxen with human faces, and children of men with oxen heads." But out of this chaos came, finally, we are led to infer, a harmonious aggregation of parts, producing ultimately the perfected organisms that we see. Unfortunately the preserved portions of the writings of Empedocles do not enlighten us as to the precise way in which final evolution was supposed to be effected; although the idea of endless experimentation until natural selection resulted in survival of the fittest seems not far afield from certain of the poetical a.s.sertions. Thus: "As divinity was mingled yet more with divinity, these things (the various members) kept coming together in whatever way each might chance." Again: "At one time all the limbs which form the body united into one by love grew vigorously in the prime of life; but yet at another time, separated by evil Strife, they wander each in different directions along the breakers of the sea of life. Just so is it with plants, and with fishes dwelling in watery halls, and beasts whose lair is in the mountains, and birds borne on wings."(17)

All this is poetry rather than science, yet such imaginings could come only to one who was groping towards what we moderns should term an evolutionary conception of the origins of organic life; and however grotesque some of these expressions may appear, it must be admitted that the morphological ideas of Empedocles, as above quoted, give the Sicilian philosopher a secure place among the antic.i.p.ators of the modern evolutionist.

VII. GREEK SCIENCE IN THE EARLY ATTIC PERIOD

We have travelled rather far in our study of Greek science, and yet we have not until now come to Greece itself. And even now, the men whose names we are to consider were, for the most part, born in out-lying portions of the empire; they differed from the others we have considered only in the fact that they were drawn presently to the capital. The change is due to a most interesting sequence of historical events. In the day when Thales and his immediate successors taught in Miletus, when the great men of the Italic school were in their prime, there was no single undisputed Centre of Greek influence. The Greeks were a disorganized company of petty nations, welded together chiefly by unity of speech; but now, early in the fifth century B.C., occurred that famous attack upon the Western world by the Persians under Darius and his son and successor Xerxes. A few months of battling determined the fate of the Western world. The Orientals were hurled back; the glorious memories of Marathon, Salamis, and Plataea stimulated the patriotism and enthusiasm of all children of the Greek race. The Greeks, for the first time, occupied the centre of the historical stage; for the brief interval of about half a century the different Grecian princ.i.p.alities lived together in relative harmony. One city was recognized as the metropolis of the loosely bound empire; one city became the home of culture and the Mecca towards which all eyes turned; that city, of course, was Athens. For a brief time all roads led to Athens, as, at a later date, they all led to Rome. The waterways which alone bound the widely scattered parts of h.e.l.las into a united whole led out from Athens and back to Athens, as the spokes of a wheel to its hub. Athens was the commercial centre, and, largely for that reason, it became the centre of culture and intellectual influence also. The wise men from the colonies visited the metropolis, and the wise Athenians went out to the colonies.

Whoever aspired to become a leader in politics, in art, in literature, or in philosophy, made his way to the capital, and so, with almost bewildering suddenness, there blossomed the civilization of the age of Pericles; the civilization which produced aeschylus, Sophocles, Euripides, Herodotus, and Thucydides; the civilization which made possible the building of the Parthenon.

ANAXAGORAS

Sometime during the early part of this golden age there came to Athens a middle-aged man from Clazomenae, who, from our present stand-point, was a more interesting personality than perhaps any other in the great galaxy of remarkable men a.s.sembled there. The name of this new-comer was Anaxagoras. It was said in after-time, we know not with what degree of truth, that he had been a pupil of Anaximenes. If so, he was a pupil who departed far from the teachings of his master. What we know for certain is that Anaxagoras was a truly original thinker, and that he became a close friend--in a sense the teacher--of Pericles and of Euripides. Just how long he remained at Athens is not certain; but the time came when he had made himself in some way objectionable to the Athenian populace through his teachings. Filled with the spirit of the investigator, he could not accept the current conceptions as to the G.o.ds. He was a sceptic, an innovator. Such men are never welcome; they are the chief factors in the progress of thought, but they must look always to posterity for recognition of their worth; from their contemporaries they receive, not thanks, but persecution. Sometimes this persecution takes one form, sometimes another; to the credit of the Greeks be it said, that with them it usually led to nothing more severe than banishment. In the case of Anaxagoras, it is alleged that the sentence p.r.o.nounced was death; but that, thanks to the influence of Pericles, this sentence was commuted to banishment. In any event, the aged philosopher was sent away from the city of his adoption. He retired to Lampsacus. "It is not I that have lost the Athenians," he said; "it is the Athenians that have lost me."