ANIMAL INSTINCTS. 153 



this point, is an instantia crucis, expounding better 

 than any other animal that strange blending of reason, 

 habits, instincts, and affections through which he comes 

 into such close alliance with man, and illustrating at 

 the same time the various affinities by which the latter 

 is linked to inferior grades of the animal world. 



This relation of habits and instincts will at once be 

 seen as one of consummate importance to the whole 

 question before us. I have treated of it at some 

 length in the chapter before alluded to, and shall 

 here add only a few remarks in further illustration. 

 Where the origin of instincts is the problem every 

 illustration is of value, and not least those which con- 

 verge from different points upon common truth. 



The definition of habit, as a mere expression of 

 fact, is simple enough, and it may be carried far down 

 into the animal world. But complicated with the 

 functions of the will, as habits are, both in their origin 

 and progress, it becomes far more difficult to describe 

 or decipher them. In truth, this single word of 

 will, so familiar to common speech, has been prolific 

 of doubt and dispute in every part of philosophy. 

 Though the mind of man especially here becomes the 

 subject of illustration, it is not easy for the conscious- 

 ness so to analyse its own workings as to separate the 

 pure act of will from the other complex machinery of 

 our mental nature. I have dwelt elsewhere on the 

 psychological fact, as important practically as in 

 theory, that numerous automatic involuntary acts, 

 mental and corporeal, have their origin in acts pri- 

 marily of the will, becoming assimilated in the end, 



