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 e:cplanation 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 ol formal logic as a testing ma- 

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

 from error. 



