v THE PHILOSOPHY OF BIRDS' NESTS 117 



to be washed away by a heavy rain and their young ones 

 destroyed. 



Conclusion 



A fair consideration of all these facts will, I think, fully 

 support the statement with which I commenced, and show 

 that the chief mental faculties exhibited by birds in . the con- 

 struction of their nests are the same in kind as those mani- 

 fested by mankind in the formation of their dwellings. These 

 are, essentially, imitation, and a slow and partial adaptation 

 to new conditions. To compare the work of birds with the 

 highest manifestations of human art and science is totally 

 beside the question. I do not maintain that birds are gifted 

 with reasoning faculties at all approaching in variety and 

 extent to those of man. I simply hold that the phenomena 

 presented by their mode of building their nests, when fairly 

 compared with those exhibited by the great mass of mankind 

 in building their houses, indicate no essential difference in the 

 kind or nature of the mental faculties employed. If instinct 

 means anything, it means the capacity to perform some com- 

 plex act without teaching or experience. It implies not only 

 innate ideas but innate knowledge of a very definite kind, and, 

 if established, would overthrow Mr. Mill's sensationalism and 

 all the modern philosophy of experience. That the existence 

 of true instinct may be established in other cases is not 

 impossible ; but in the particular instance of birds' nests, which 

 is usually considered one of its strongholds, I cannot find a 

 particle of evidence to show the existence of anything beyond 

 those lower reasoning and imitative powers which animals 

 are universally admitted to possess. 



