Science

We have seen that the Ptolemaic astronomy, which was the accepted doctrine throughout the Middle Ages, taught that the earth is round. Doubtless there was a popular opinion current which regarded the earth as flat, but it must be understood that this opinion had no champions among men of science during the Middle Ages. When, in the year 1492, Columbus sailed out to the west on his memorable voyage, his expectation of reaching India had full scientific warrant, however much it may have been scouted by certain ecclesiastics and by the average man of the period.

Throughout classical antiquity Egyptian science was famous. We know that Plato spent some years in Egypt in the hope of penetrating the alleged mysteries of its fabled learning; and the story of the Egyptian priest who patronizingly assured Solon that the Greeks were but babes was quoted everywhere without disapproval. Even so late as the time of Augustus, we find Diodorus, the Sicilian, looking back with veneration upon the Oriental learning, to which Pliny also refers with unbounded respect.

Before we turn specifically to the new world of the west, it remains to take note of what may perhaps be regarded as the very greatest achievement of ancient science. This was the analysis of speech sounds, and the resulting development of a system of alphabetical writing. To comprehend the series of scientific inductions which led to this result, we must go back in imagination and trace briefly the development of the methods of recording thought by means of graphic symbols. In other words, we must trace the evolution of the art of writing.

Herodotus, the Father of History, tells us that once upon a time—which time, as the modern computator shows us, was about the year 590 B.C. —a war had risen between the Lydians and the Medes and continued five years. "In these years the Medes often discomfited the Lydians and the Lydians often discomfited the Medes (and among other things they fought a battle by night); and yet they still carried on the war with equally balanced fortitude. In the sixth year a battle took place in which it happened, when the fight had begun, that suddenly the day became night.

Diogenes Laertius tells a story about a youth who, clad in a purple toga, entered the arena at the Olympian games and asked to compete with the other youths in boxing. He was derisively denied admission, presumably because he was beyond the legitimate age for juvenile contestants. Nothing daunted, the youth entered the lists of men, and turned the laugh on his critics by coming off victor. The youth who performed this feat was named Pythagoras.

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.

Doubtless it has been noticed that our earlier scientists were as far removed as possible from the limitations of specialism. In point of fact, in this early day, knowledge had not been classified as it came to be later on. The philosopher was, as his name implied, a lover of knowledge, and he did not find it beyond the reach of his capacity to apply himself to all departments of the field of human investigation.

We are entering now upon the most important scientific epoch of antiquity. When Aristotle and Theophrastus passed from the scene, Athens ceased to be in any sense the scientific centre of the world. That city still retained its reminiscent glory, and cannot be ignored in the history of culture, but no great scientific leader was ever again to be born or to take up his permanent abode within the confines of Greece proper. With almost cataclysmic suddenness, a new intellectual centre appeared on the south shore of the Mediterranean.

Just about the time when Hipparchus was working out at Rhodes his puzzles of celestial mechanics, there was a man in Alexandria who was exercising a strangely inventive genius over mechanical problems of another sort; a man who, following the example set by Archimedes a century before, was studying the problems of matter and putting his studies to practical application through the invention of weird devices. The man's name was Ctesibius. We know scarcely more of him than that he lived in Alexandria, probably in the first half of the second century B.C.

We have seen that the third century B.C. was a time when Alexandrian science was at its height, but that the second century produced also in Hipparchus at least one investigator of the very first rank; though, to be sure, Hipparchus can be called an Alexandrian only by courtesy. In the ensuing generations the Greek capital at the mouth of the Nile continued to hold its place as the centre of scientific and philosophical thought.