62 BIOLOGICAL SOCIETY OF WASHINGTON. 



Now such a system of philosophy, a mythology, is found in every 

 savage and barbaric tribe of the world. 



But there came a time in the history of mankind when some of 

 the peoples changed their philosophy their explanation of the 

 phenomena of the universe by changing their methods of reason 

 ing. 



ORIGIN OF METAPHYSIC PHILOSOPHY. 



From three to two thousand years ago Europe, Asia, and Africa 

 established a commerce in ideas an exchange in philosophies 

 carried on by the navigation of the Mediterranean. During that 

 and some previous time there were built on the shores of this sea 

 many cities. Through the building of these cities, and through 

 the industries and arts which sprang up therewith, society was re 

 organized, and placed upon a new basis tribal society developed 

 into national society barbarism into civilization. 



The peoples of these cities spoke diverse languages, and enter 

 tained diverse mythologic philosophies. Through the intercourse 

 which sprang up between them each learned of the philosophy of 

 the other, and the scholars of that day attempted to discover in all 

 of these diverse mythologies a common body of truth upon the 

 theory then, widely accepted, that they had all sprung from a com 

 mon source a primitive philosophy itself the truth and that all 

 the philosophies then existing were degenerations therefrom. This 

 line of investigation led to a curious result. 



All of the mythologies of the cities of the Mediterranean were 

 found to be baseless each a fabric of poetic but superficial analo 

 gies. In the mental activity of that time many new philosophies 

 were proposed, diverse and contradictory, and the wisest philoso 

 phers said, "How shall we know the truth?" And they endeav 

 ored to discover some criterion by which truth should be known. 

 This resulted in the development of formal logic as a testing ma 

 chine into which opinions were put for the purpose of sifting truth 

 from error. 



