THE GOLDEN AGE OF GREECE 63 



if there is anything to know." Galileo, himself of a highly scepti- 

 cal turn of mind, refers with approval to Democritus, and it is 

 probably on this side, i.e. by exemplification of the critical spirit, 

 that Democritus rendered his greatest service. His positive con- 

 tributions to science, even in atomism, were apparently neither 

 novel nor important. Democritus explained the Milky Way 

 as composed of a vast number of small stars, but to his dis- 

 ciple, Metrodorus of Chios, it was a former path of the Sun. 



THE BEGINNINGS OF RATIONAL MEDICINE. HIPPOCRATES OF 

 Cos. Before the middle of the fifth century B.C., science in 

 the healing art had no existence. Excepting among a few of the 

 more enlightened, sacrifices and other appeals to the gods still 

 characterized medicine as a priestly rather than a scientific pro- 

 fession, while the prevailing ignorance of anatomy and physiology 

 made rational treatment of the sick difficult if not impossible. 

 Alcmaeon, in the previous century, had taken some steps in the 

 right direction, proving for example that the sperm does not 

 originate, as was currently believed, in the spinal marrow, and that 

 the brain is the organ of mind, and advancing a naturalistic theory 

 of disease which seems to foreshadow that of his great successor 

 Hippocrates. 



Two island centres of medical lore (they can hardly be called 

 medical schools), both of the cult of Asclepias, existed in the 

 southeastern ^Egean, viz. Cos and Cnidus, and on the former was 

 born, in 460 B.C., Hippocrates, "the Father of Medicine," in the 

 next century already characterized by Aristotle as "the Great." 

 Of his life, education, practice, and writings comparatively little is 

 certainly known. Many of the writings attributed to him are of 

 doubtful authenticity and are more safely assigned to the Hip- 

 pocratic "school." Enough remain, however, especially when 

 added to the references by later authors to him and to his sayings 

 and to his methods of practice, to make it clear that in every re- 

 spect Hippocrates was worthy of the lofty reputation with which 

 his name has come down to us after five and twenty centuries. 



And yet it is not for the practical arts of medicine or any of its 

 basic sciences that Hippocrates did his most famous work. It 



