8 PHYSICAL EXPRESSION. 



The primary assumption is made that mentation 



//is dependent upon the material structure of the 



body, and that the structure, properties, and 



functions of that body are the result of external 



forces. 



When any principles are laid down for practical 

 guidance in this inquiry,* the endeavour has been 

 made to show that they are widespread " uni- 

 formities in the operations of nature," or laws 

 applicable to questions outside the proper scope of 

 this work, and that they are laws or uniformities 

 in the operation of nature of wide action in various 

 biological problems. The endeavour has also been 

 made to show that these laws, as defined and 

 explained, give the foundations for a .true experi- 

 mental inquiry, and that they are in harmony with 

 many of the laws defined in biology, in psycho- 

 logy, and physiology, also in some cases with the 

 laws of sociology and human social life. 



It seems to me a matter of great importance to 

 study the attributes of every property observed, 

 the time, quantity, and kind of property ; in some 

 cases the " kind " can be described in terms of time 

 and quantity. This is entered upon and illustrated 

 in chap. xvi. 



The principles and methods of analysis used (see 

 chap, xv.) are the outcome of daily observations, 

 and have been applied over and over again to many 

 cases in dealing with my living patients. This is 

 mentioned in the hope that others may be induced 

 to see whether these principles are in accord with 



* See specially chaps, ii.-iv. 



