PREFACE xvii 



practically coeval with Caesar, Constantine, Charlemagne, 

 St. Louis, Charles V, and Victoria; Bacon, Newton, and 

 Darwin are but the younger contemporaries of Thales, 

 Plato, and Aristotle." 



Perhaps this short survey of a great subject will seem 

 ambitious to many. But evolution means the slow un- 

 folding of hidden potentialities. We must study pre- 

 historic man as well as ancient man because the changes 

 wrought in social evolution are so gradual that it is only 

 by examining the long period that we can become con- 

 scious of their real significance. The change that is ob- 

 servable at the end of a long period is indistinguishable 

 in the briefer interval. This is the author's justification 

 for attempting to present as an organic whole a subject 

 the divisions of which specialists often find quite baffling. 

 In the effort to classify and generalize a great body of 

 knowledge, the "clumsy forceps of our minds" always 

 crush the truth a little and mar it. Yet there is a genuine 

 gain from the very effort to attain perspective, although 

 violence may be done to the strict accuracy of certain 

 details. The artist suppresses many things in order to 

 strengthen the general impression that the picture is to 

 make. Thus, perhaps, the scientist can learn from his 

 fellow seeker after truth. 



The author does not regard the book as final in any 

 sense and would welcome the criticism of errors or sug- 

 gestions by which the work may be improved. 



The illustrations have been carefully selected and ar- 

 ranged with a view to illuminate certain points made in 

 the text which the average student would otherwise be 

 unable to visualize. The author would have considerable 

 emphasis placed upon this use of the illustrations since 

 each has been chosen for a definite purpose. 



