284 Darwin, and after Darwin. 
cases of adaptation which are to be met with in organic 
nature, as intelligent design could be. Hence, our 
choice as between these two hypotheses must be go- 
verned by a study of all collateral circumstances ; that 
is to say, by a study of the evidences in favour of the 
physical explanation. To this study, therefore, we 
shall now address ourselves, in the course of the follow- 
ing chapters. 
