CH. ii NEED OF DEFINITIONS 67 



to which it relates. It takes a much 

 larger view of the problems of Biology 

 than is generally taken, and it deals 

 with them by a method which is ex- 

 cellent, so far as he carries it, and which 

 we can all take up and follow farther 

 than the point at which he stops. That 

 method is to insist on a clear definition 

 of the words and phrases used in our 

 biological data and speculations. No 

 method could be more admirable than 

 this. It is one for which I have myself 

 a great predilection, and have continu- 

 ally used in all difficult subjects of 

 inquiry. Such, pre-eminently, are the 

 problems presented by the nature and 

 history of organic life. I propose, there- 

 fore, in these pages to accept Mr. 

 Spencer's method, and to examine what 

 light can come from it on this most 

 intricate of all subjects. 



The leading idea of Mr. Spencer's 



