|THE EARLIEST PREDECESSORS OF COPERNICUS|
THE first glimmerings of perception that presage the discovery of great truths, whether coeval with, or long antecedent to complete apprehension, possess for most minds a fascinating interest. Whether it be abstract ideas, epoch-making inventions or discoveries of fundamental laws, such as gravitation or evolution, matters not; the names of those who have contributed largely toward intellectual progress, even if they fell short of the whole truth—if they merely prepared the way for final discovery—become universally reverenced, or acquire at least a romantic interest, by virtue of their heraldry. In natural science, as elsewhere, it is right and fitting that a high place be reserved for the advance prophets who have preceded the great expounders of Nature's truths.
By common consent of mankind, the Copernican cosmogony ranks as one of the immortal triumphs of genius, whence it follows that not only the monk of Frauenburg, and the scarcely less famous defenders of his theory, but also his remote predecessors, are entitled to an exalted position amongst those favored mortals who have been permitted, in one age or another, to wrest from Nature the solution of her deepest mysteries. Yet because of the absolute originality of the great sixteenth-century astronomer's discovery; because, furthermore, the anticipators of his theory failed to convert the world to their belief; and because Copernicus himself knew nothing of his real predecessors, it has come about that too little credit is commonly bestowed upon ancient forerunners of our modern system.
There is abundant and undisputed testimony to show that in the minds of at least two astronomers prior to the Christian era, namely, Aristarchus of Samos, and Seleuchus the Chaldæan, the essential features of our modern system were clearly recognized, and elaborated not only into a working hypothesis, but into a valid explanation of the universe. It is impossible to view this achievement in its manifold relations to human progress, without being impressed with the pathetic and remarkable fact that a ray of divine intelligence should have shone forth for an instant in that far-off period, kindling here and there a momentary spark; sparks that, although revealing the true order of the cosmos, were not finally to illumine the world until after the lapse of centuries.
No demonstration is necessary to show that the beginning of astronomical knowledge is a subject in which all intelligent persons