LITTLE BLUE BOOK NO. =608= Edited by E. Haldeman-Julius The Origin and Development of the Atomic Theory Maynard Shipley HALDEMAN-JULIUS COMPANY GIRARD, KANSAS Copyright, 1924 Haldeman-Julius Company PRINTED IN THE UNITED STATES OF AMERICA THE ORIGIN AND DEVELOPMENT OF THE ATOMIC THEORY CONTENTS PAGE CHAPTER I—THE PYTHAGOREAN ATOMISTS 5 CHAPTER II—THE MATERIALISTIC ATOMISTS: LEUCIPPUS AND DEMOCRITUS 22 CHAPTER III—THE ELEATIC VIEW 37 CHAPTER IV—EPICURUS AND LUCRETIUS 51 CHAPTER V—POST-CLASSICAL ATOMISM 59 THE ORIGIN AND DEVELOPMENT OF THE ATOMIC THEORY CHAPTER I THE PYTHAGOREAN ATOMISTS THE SIGNIFICANCE OF THE ATOMIC THEORY It is safe to say that there is no more romantic story in the history of science than that of the origin and development of the atomic theory of matter. Dr. Robert A. Millikan has said that the physical principles laid down by Leucippus in the fifth century before our era might, with a few modifications and omissions, “almost pass muster today” (“The Electron,” Page 7). The importance to modern students of sound knowledge of the teachings of the ancient Atomists was emphasized by Sir William Osler (1829-1919), who even went so far as to say that “the student of physics may know Crookes’ tubes and their relation to Roentgen, but he cannot have a true conception of the atomic theory without a knowledge of Democritus; and the exponent of Madame Curie and of Sir J. J. Thomson will find his happiest illustrations from the writings of Lucretius”[1]--the Roman exponent of Epicurus (342-270 B. C.), who revived the atomic theory of Leucippus and Democritus, despite the adverse criticisms hurled at this doctrine by the great Aristotle. Le Sage observed that “if Epicurus had had but a part of the geometrical knowledge of his contemporary Euclid, and conceptions of cosmogony the same as many then living, he might have discovered the laws of universal gravity, and not only the laws, but, what was the despair of Newton, its mechanical cause” (“_Lucrèce Newtonien_,” Berlin Academy, 1782).