Oy INSTINCT IN MAN AND ANIMALS. 205 



be so self-evident that they may be taken for granted. 

 No one has ever yet obtained the eggs of some bird 

 which builds an elaborate nest, hatched these eggs by 

 steam or under a quite distinct parent, placed them 

 afterwards in an extensive aviary or covered garden, 

 where the situation and the materials of a nest simi- 

 lar to that of the parent birds may be found, and then 

 seen what kind of nest* these birds would build. If 

 under these rigorous conditions they choose the same 

 materials, the same situation, and construct the nest 

 in the same way and as perfectly as their parents did, 

 instinct would be proved in their case ; now it is only 

 assumed, and assumed, as I shall show further on, 

 without any sufficient reason. So, no one has ever 

 carefully taken the pupse of a hive of bees out of the 

 comb, removed them from the presence of other bees, 

 and loosed them in a large conservatory with plenty 

 of flowers and food, and observed what kind of cells 

 they would construct. But till this is done, no one 

 can say that bees build without instruction, no one 

 can say that with every new swarm there are no bees 

 older than those of the same year, who may be the 

 teachers in forming the new comb. Now, in a scien- 

 tific inquiry, a point which can be proved should not 

 be assumed, and a totally unknown power should not 

 be brought in to explain facts, when known powers 

 may be sufficient. For both these reasons I decline to 

 accept the theory of instinct in any case where all 

 other possible modes of explanation have not been 

 exhausted. 



