INTRODUCTORY 



view, which regards them as in motion. During 

 the past generation this principle has been im- 

 measurably fruitful. The reader who remembers 

 Spencer's definition of science as "organized 

 knowledge," and who sees in politics and theology 

 in so far as they are true politics and theology 

 sciences as worthy of the name as are astronomy 

 and biology, will read their full significance into 

 these recent words 1 of Sir William Huggins, the 

 illustrious student who has taught us that the 

 stars are made of the same stuff as this paper or 

 the tissue of the reader's eye : 



"On one central eminence, dominating alike the past, 

 the present, and the future, Science has for some years 

 firmly intrenched herself the position that through all 

 the ages the Cosmos has advanced, and is still advancing, 

 by a process of orderly evolution." 



In establishing the term evolution as an inde- 

 feasible part of the intellectual heritage of all com- 

 ing time, Herbert Spencer accomplished a lesser 

 and a greater thing. The lesser thing was the 

 statement, in terms which we have yet to consider, 

 of the laws which are observed in all change. In 

 material and mental phenomena alike change is 

 not a "law of higgledy-piggledy," as the once 

 famous geologist Sedgwick pained Darwin by 

 describing the law of natural selection, but pro- 

 ceeds on lines determined by the very nature of 



1 Spoken at a dinner of the Royal Society, 

 13 



