Edward Huntington Williams

A History of Science (Vol. 1-5)


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had been pioneers among those venturesome colonists who reached out into distant portions of the world, and made homes for themselves in much the same spirit in which colonists from Europe began to populate America some two thousand years later. In general, colonists from the different parts of Greece localized themselves somewhat definitely in their new homes; yet there must naturally have been a good deal of commingling among the various families of pioneers, and, to a certain extent, a mingling also with the earlier inhabitants of the country. This racial mingling, combined with the well-known vitalizing influence of the pioneer life, led, we may suppose, to a more rapid and more varied development than occurred among the home-staying Greeks. In proof of this, witness the remarkable schools of philosophy which, as we have seen, were thus developed at the confines of the Greek world, and which were presently to invade and, as it were, take by storm the mother-country itself.

      As to the personality of these pioneer philosophers of the West, our knowledge is for the most part more or less traditional. What has been said of Thales may be repeated, in the main, regarding Pythagoras, Parmenides, and Empedocles. That they were real persons is not at all in question, but much that is merely traditional has come to be associated with their names. Pythagoras was the senior, and doubtless his ideas may have influenced the others more or less, though each is usually spoken of as the founder of an independent school. Much confusion has all along existed, however, as to the precise ideas which were to be ascribed to each of the leaders. Numberless commentators, indeed, have endeavored to pick out from among the traditions of antiquity, aided by such fragments, of the writing of the philosophers as have come down to us, the particular ideas that characterized each thinker, and to weave these ideas into systems. But such efforts, notwithstanding the mental energy that has been expended upon them, were, of necessity, futile, since, in the first place, the ancient philosophers themselves did not specialize and systematize their ideas according to modern notions, and, in the second place, the records of their individual teachings have been too scantily preserved to serve for the purpose of classification. It is freely admitted that fable has woven an impenetrable mesh of contradictions about the personalities of these ancient thinkers, and it would be folly to hope that this same artificer had been less busy with their beliefs and theories. When one reads that Pythagoras advocated an exclusively vegetable diet, yet that he was the first to train athletes on meat diet; that he sacrificed only inanimate things, yet that he offered up a hundred oxen in honor of his great discovery regarding the sides of a triangle, and such like inconsistencies in the same biography, one gains a realizing sense of the extent to which diverse traditions enter into the story as it has come down to us. And yet we must reflect that most men change their opinions in the course of a long lifetime, and that the antagonistic reports may both be true.

      True or false, these fables have an abiding interest, since they prove the unique and extraordinary character of the personality about which they are woven. The alleged witticisms of a Whistler, in our own day, were doubtless, for the most part, quite unknown to Whistler himself, yet they never would have been ascribed to him were they not akin to witticisms that he did originate—were they not, in short, typical expressions of his personality. And so of the heroes of the past. "It is no ordinary man," said George Henry Lewes, speaking of Pythagoras, "whom fable exalts into the poetic region. Whenever you find romantic or miraculous deeds attributed, be certain that the hero was great enough to maintain the weight of the crown of this fabulous glory."(1) We may not doubt, then, that Pythagoras, Parmenides, and Empedocles, with whose names fable was so busy throughout antiquity, were men of extraordinary personality. We are here chiefly concerned, however, neither with the personality of the man nor yet with the precise doctrines which each one of them taught. A knowledge of the latter would be interesting were it attainable, but in the confused state of the reports that have come down to us we cannot hope to be able to ascribe each idea with precision to its proper source. At best we can merely outline, even here not too precisely, the scientific doctrines which the Italic philosophers as a whole seem to have advocated.

      First and foremost, there is the doctrine that the earth is a sphere. Pythagoras is said to have been the first advocate of this theory; but, unfortunately, it is reported also that Parmenides was its author. This rivalship for the discovery of an important truth we shall see repeated over and over in more recent times. Could we know the whole truth, it would perhaps appear that the idea of the sphericity of the earth was originated long before the time of the Greek philosophers. But it must be admitted that there is no record of any sort to give tangible support to such an assumption. So far as we can ascertain, no Egyptian or Babylonian astronomer ever grasped the wonderful conception that the earth is round. That the Italic Greeks should have conceived that idea was perhaps not so much because they were astronomers as because they were practical geographers and geometers. Pythagoras, as we have noted, was born at Samos, and, therefore, made a relatively long sea voyage in passing to Italy. Now, as every one knows, the most simple and tangible demonstration of the convexity of the earth's surface is furnished by observation of an approaching ship at sea. On a clear day a keen eye may discern the mast and sails rising gradually above the horizon, to be followed in due course by the hull. Similarly, on approaching the shore, high objects become visible before those that lie nearer the water. It is at least a plausible supposition that Pythagoras may have made such observations as these during the voyage in question, and that therein may lie the germ of that wonderful conception of the world as a sphere.

      To what extent further proof, based on the fact that the earth's shadow when the moon is eclipsed is always convex, may have been known to Pythagoras we cannot say. There is no proof that any of the Italic philosophers made extensive records of astronomical observations as did the Egyptians and Babylonians; but we must constantly recall that the writings of classical antiquity have been almost altogether destroyed. The absence of astronomical records is, therefore, no proof that such records never existed. Pythagoras, it should be said, is reported to have travelled in Egypt, and he must there have gained an inkling of astronomical methods. Indeed, he speaks of himself specifically, in a letter quoted by Diogenes, as one who is accustomed to study astronomy. Yet a later sentence of the letter, which asserts that the philosopher is not always occupied about speculations of his own fancy, suggesting, as it does, the dreamer rather than the observer, gives us probably a truer glimpse into the philosopher's mind. There is, indeed, reason to suppose that the doctrine of the sphericity of the earth appealed to Pythagoras chiefly because it accorded with his conception that the sphere is the most perfect solid, just as the circle is the most perfect plane surface. Be that as it may, the fact remains that we have here, as far as we can trace its origin, the first expression of the scientific theory that the earth is round. Had the Italic philosophers accomplished nothing more than this, their accomplishment would none the less mark an epoch in the progress of thought.

      That Pythagoras was an observer of the heavens is further evidenced by the statement made by Diogenes, on the authority of Parmenides, that Pythagoras was the first person who discovered or asserted the identity of Hesperus and Lucifer—that is to say, of the morning and the evening star. This was really a remarkable discovery, and one that was no doubt instrumental later on in determining that theory of the mechanics of the heavens which we shall see elaborated presently. To have made such a discovery argues again for the practicality of the mind of Pythagoras. 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 asserted that he was the first person who introduced measures and weights among the Greeks, this assertion 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