THE DOCTRINE OF PROGRESSIVE DEVELOPMENT. 265 



be left out of account in the few remarks which will 

 here be made as to its general scope and teaching. 



The * Vestiges ' not only dealt with the origin of the 

 various forms under which vitality has been manifested 

 in the past, or is exhibited at the present day ; but it also 

 took up the much wider and much more inscrutable 

 problem of the origin of life itself. It was therefore 

 more than simply an attempt to explain the origin of 

 'species.' The work is remarkable for the ability which 

 it displays in the handling of general principles, for the 

 closeness of its reasoning, for the clearness with which 

 fallacies are detected and exposed, for the lucidity of 

 its style, and for the wealth of its suggestions. It is, 

 nevertheless, inadequate for the purpose which the writer 

 proposed to himself as the object of his labours. It is, 

 namely, unmistakably, the work of a writer who had 

 mastered the general facts and principles of zoology and 

 the kindred sciences, but who at the same time was 

 without that minute knowledge of biological science 

 which can be obtained in no other way save by long- 

 continued and rigidly conducted first-hand investigation 

 into the phenomena presented by living beings. No fact, 

 indeed, stands out more clearly in the whole history 

 of science than the insufficiency of a merely general 

 knowledge for the establishment of generalisations of any 

 kind. Only the worker whose mind is stored with the 

 minutest details of his subject can safely enter upon 

 the task of generalisation. 



Having premised so much, we may briefly sketch the 

 conclusions which are set forth in the 'Vestiges.' After 

 a general review of the relations of the earth to the 



