president's address. 839 



make progress on truly scientific lines, continue to bring all the 

 facts of observation and experiment under the dominant idea of 

 mechanism or physical causation, yet we are continually forced 

 to recognise the incompetence of the mechanical principle to 

 satisfy the intellectual demand for a full comprehension of the 

 significance of living process. And this inadequacy becomes the 

 more glaring as the phenomena to be investigated approximate 

 more and more to the character of manifestations of conscious 

 intellectual activity. 



The difficulty arising out of the confusion of two' points of 

 view, emerges in one of its most impressive and characteristic 

 forms in the efforts to apply the principle of evolution, in its guise 

 as a principle of natural history, to the manifestations of human 

 activity in social institutions and laws of conduct. 



It has indeed been one of the triumphs of the historical method 

 to have largely " emancipated our views of the past from their 

 bondage to the ideas of the present" by means of "the concep- 

 tion of the evolution of man by interaction with his environment." 



In its more extreme form, however, this idea of human evolu- 

 tion has been interpreted on the lines of organic evolution 

 generally, as a sequence of natural phenomena causally connected 

 by the aid of the principles of variation, heredity and natural 

 selection. 



Earlier in this address I have referred to^the representation of 

 natural selection operating upon indefinite variation, as a means of 

 explaining organic adaptation as a purely naturalistic process. 



Even as applied to the lower stages of organisation, we saw 

 that this reduction could not be regarded as having been actually 

 effected, so long as the residual phenomenon of variation 

 remained unexplained. Evolutional adaptation ^^still remains 

 dependent upon an inherent " spontaneous," or at least an 

 unexplained variability. 



And when we come to apply the conception of evolution to the 

 products of conscious human activity, we find ^ourselves upon 

 still more uncertain ground. 



