832 THE POPULAR SCIENCE MONTHLY. 



The interchange of products is necessarily accompanied, to some 

 extent, with an interchange of ideas. The feeling of curiosity 

 reached a high point of development among the Greeks. It was 

 the thirst to know which sent old Herodotus into the heart of hos- 

 tile nations, and which is sending thousands to-day, in quest of 

 knowledge, through the highways and byways of the world. 

 Greece first fairly set in train this mental commerce. But the 

 peaceful interchange of thought has grown immensely since the 

 Grecian days, the whole world is being ransacked for old ideas 

 and new experiences, and the thought stock of the several nations 

 is gradually becoming a general thought stock, the freehold prop- 

 erty of the world. 



It is unquestionable that trading nations which have reached 

 a certain degree of mental advancement are efficient agents in 

 propagating civilization. There are several instances of this in 

 the history of the past, but in most of such cases commerce was 

 aided in its effects by colonization. It was not the movement of 

 a few isolated merchants, but of extensive colonies, that produced 

 the commingling of thought, with its useful results. The Phoeni- 

 cians were the first great trading nation of whom we have any 

 record ; and they were the first to emerge into civilization under 

 peaceful influences. The Greeks followed them in this field, and 

 the lofty enlightenment of Athens is more to be ascribed to its com- 

 mercial activity, its colonizing spirit, and its free reception of the 

 best minds from other nations than to its warlike vigor and suc- 

 cess. In more modern times we have had successively the Vene- 

 tians, the Genoese, the Spaniards, the Portuguese, the Dutch, and 

 the English advancing into commercial activity and, with it, into 

 phases of enlightened energy in close accordance with the width 

 and character of their commerce. 



We no longer have to fight our way into the thoughts of the 

 world. Every step of mental development made by an exterior 

 people is becoming our own without need of its being taken by 

 violence. We pick and choose at will throughout the races of 

 mankind, digest what we thus consume, assimilate the good, avoid 

 the evil, and widen our minds continually in the process. If it is 

 something to learn what good exists unknown to us, it is also 

 something to know what evil exists. A knowledge of good and 

 evil alike is essential to human progress. And this process is in 

 no sense a destructive one. In war not only possessions are de- 

 stroyed, but to some extent ideas as well. It is only the remnants 

 that enrich the conquering race the methods of material produc- 

 tion, the religions and philosophies, the rigid laws and customs 

 among which they settle down and which they are forced to as- 

 similate. 



Modern progress is not gained by the gathering up of the relics 



