Mechanism, Vitalism, and Teleology 365 



we observe the purposive actions of animals, for example 

 crows dropping mussels on rocks to break them open, cats 

 turning buttons to open doors, or horses unlatching gates, 

 it is evident that we are here dealing with the same funda- 

 mental problem that we have in human purpose. Finally, 

 even non-conscious and purely instinctive acts, that are pur- 

 posive, belong in the same category; for example, the mat- 

 ing, nest-building, brooding, and care of young on the part 

 of birds, or similar reproductive habits of mammals, show 

 instinctive, but not perceptual purpose. In man only, so 

 far as we know, does purposive action at certain times rise 

 into the field of consciousness, but most of his activities are 

 non-conscious, although they are purposive. All such phe- 

 nomena, from conscious purpose at one extreme to instinc- 

 tive reactions and to tropisms at the other, seem to be fun- 

 damentally akin, and if mechanism fails to explain any of 

 them it probably fails with all ; if tropisms and instincts are 

 entirely explicable on mechanistic grounds, it is probable 

 that even perceptual purpose may be so explained. 



In commenting upon the fact that adaptations are mech- 

 anisms for securing the persistence of organisms, Roux 1 

 says: "Persistence is not an aim of living things but an in- 

 dispensably necessary condition. Life cannot suddenly arise 

 anew, but if it exists it must be preserved, and so must before 

 all be capable of persisting, otherwise it disappears. This is 

 no aim but a direct necessity of its existence." 



But after all, the real question is how living things are 

 able to meet these necessary conditions of life. It may be 

 granted that adaptations are not caused by conscious aims 

 or purposes, but their results are much the same as if they 

 were; they do attain certain desirable ends, and to this ex- 

 tent they are purposive. But results may be purposive while 



'Arch. Entwick. Mech. Bd. 26, 1908. 



