INTRODUCTION. 63 



intellectual, artistic, and practical achievements of the age 

 rest. 



It would thus appear as if an account of the thought of s. 



Inquiry into 



the century might naturally divide itself into two separate j^^t of 

 investigations. In the first place, we should regard thought tw^ 

 merely as a means to an end, as the method adopted to 

 attain a certain purpose, be it practical or theoretical. It 

 would mean the peculiar kind of reasoning which has been 

 employed in the search for knowledge or in its useful 

 application. As all reasoning starts from certain assump- 

 tions, called premisses, or principles, or axioms, and pro- 

 gresses from these by certain methods, this portion of our 

 task would divide itself again into a statement of the 

 principles which underlie, and an account of the methods 

 which have guided, theoretical and practical reasoning. 

 But thought does not exist merely for the sake of in- 

 creasing our knowledge of things and of applying this to 

 practical purposes. Occupied in this way merely, it re- 

 mains fragmentary, incomplete, and not infrequently it 

 reveals contradictions. Even those who devote themselves 

 purely to detailed research or to practical work are again 

 and again compelled to take a wider and deeper view of 

 things than their special occupation affords. One may 

 find that the methods which he is using daily become 

 useless for certain practical purposes he has in view, and 

 may thus be forced to question the principles which during 

 half his lifetime he has applied with unquestioning faith 

 in their validity and usefulness. Another may have met 

 with such success in the use of a special method of re- 

 search, that he wishes to apply it to subjects which were 

 previously handled in a different manner, or elevate it to 



