192 INSTINCT. [CHAP. VIIL 



action is performed, but not necessarily of its origin. How 

 unconsciously many habitual actions are performed, indeed not 

 rarely in direct opposition to our conscious will ! yet they may be 

 modified by the will or reason. Habits easily become associated 

 with other habits, with certain periods of time, and states of the 

 body. When once acquired, they often remain constant through- 

 out life. Several other points of resemblance between instincts 

 and habits could be pointed out. As in repeating a well-known 

 song, so in instincts, one action follows another by a sort of 

 rhythm ; if a person be interrupted in a song, or in repeating 

 anything by rote, he is generally forced to go back to recover the 

 habitual train of thought ; so P. Huber found it was with a 

 caterpillar, which makes a very complicated hammock ; for if he 

 took a caterpillar which had completed its hammock up to, 

 say. the sixth stage of construction, and put it into a hammock 

 completed up only to the third stage, the caterpillar simply 

 re-performed the fourth, fifth, and sixth stages of construction. 

 If, however, a caterpillar were taken out of a hammock made up, 

 for instance, to the third stage, and were put into one finished up 

 to the sixth stage, so that much of its work was already done 

 for it, far from deriving any benefit from this, it was much 

 embarrassed, and in order to complete its hammock, seemed forced 

 to start from the third stage, where it had left off, and thus tried 

 to complete the already finished work. 



If we suppose any habitual action to become inherited and it 

 can be shown that this does sometimes happen then the resem- 

 blance between what originally was a habit and an instinct 

 becomes so close as not to be distinguished. If Mozart, instead of 

 playing the pianoforte at three years old with wonderfully little 

 practice, had played a tune with no practice at all, he might truly 

 be said to have done so instinctively. But it would be a serious 

 error to suppose that the greater number of instincts have been 

 acquired by habit in one generation, and then transmitted by 

 inheritance to succeeding generations. It can be clearly shown 

 that the most wonderful instincts with which we are acquainted, 

 namely, those of the hive-bee and of many ants, could not possibly 

 have been acquired by habit. 



It will be universally admitted that instincts are as important 

 as corporeal structures for the welfare of each species, under its 

 present conditions of life. Under changed conditions of life, it is 

 at least possible that slight modifications of instinct might be 

 profitable to a species ; and if it can be shown that instincts do 

 vary ever so little, then I can see no difficulty in natural selection 

 preserving and continually accumulating variations of instinct to 

 any extent that was profitable. It is thus, as I believe, that all 

 the most complex and wonderful instincts have originated. As 



