12 PHYSICAL SCIENCE 



helping us to make systematic use of the 

 resources of Nature. 



Confronted with the mystery of the Universe, 

 we are driven to ask if the model our minds 

 have framed at all corresponds with the reality ; 

 if, indeed, there be any reality behind the image. 

 Such a question is a proper study of philosophy, 

 but need not necessarily be answered for the 

 model to be made or used. The whole problem 

 mankind has to face undoubtedly includes this 

 fundamental question of the ultimate nature of 

 reality, which would enter into a complete 

 explanation of every fact, even of those which 

 we regard as the simplest. This aspect of 

 the problem is the subject of that branch of 

 philosophy usually known as Metaphysics. But, 

 if we confine our attention to the phenomena 

 which our senses apprehend, and, thus restricting 

 our inquiry, examine our mental picture of Nature 

 and the relation of its parts to each other, testing 

 their correspondence or want of correspondence, 

 we are studying Natural Science. The limitation 

 indicated has not always been observed, and the 

 name of Natural Philosophy survives to remind 

 us that Natural Science is but one part of the 

 whole of conceivable knowledge. 



Philosophy may be divided into two depart- 

 ments. They are called by Broad Critical 

 Philosophy, the analysis of our fundamental 

 concepts and beliefs, and Speculative Philosophy, 

 which takes over the results of science and of 

 other modes of human experience, and, in the 

 light of all the evidence, considers the nature 

 and meaning of the Universe. 



The problem of Speculative Philosophy is 



