THEORIES OF MENTAL EVOLUTION 263 



nervous tissue, mysteriously evolved without the aid of 

 Natural Selection. 



425. So when the dragon-fly launches himself in flight it is 

 very probable he has no conscious design of seeking food, 

 however hungry he may be. Doubtless his immediate 

 impulse, his immediate desire, is to perform certain actions 

 which, as it happens, result in flight. The sight of prey 

 awakens in succession the impulse to pursue, to seize, and 

 ultimately to eat. Again, I cannot distinguish his succes- 

 sive emotions from desires. I have no means of judging his 

 instincts, of imagining his emotions, except by referring 

 them to my own, which they probably resemble to some 

 extent. I note that no instinct ever moves within me, but 

 there awakens with it a desire, which to me is indistinguish- 

 able from the instinct. Thus as a child the sporting instinct 

 was to me nothing other than a desire to sport. When I 

 was older a pretty face awakened in me emotions which 

 were certainly desires. At the present day when I am 

 hungry the smell of food awakens an emotion which I cannot 

 separate from a desire to eat. The sight of my child is apt 

 to awaken other emotions which I cannot separate from a 

 desire to perform various acts of tenderness. 1 



426. According to most authorities instinctive movements 

 should be placed in the category of reflex actions, because 

 they follow fatally the application of given stimuli. " The 

 actions we call instinctive all conform to the general reflex type ; 

 they are called forth by determinate sensory stimuli in con- 

 tact with the animal's body, or at a distance in his environ- 

 ment. The cat runs after the mouse, runs or shows fight 

 before the dog, avoids falling from walls and trees, shuns fire 

 and water, etc., not because he has any notion of life, or 

 of death, or of self, or of preservation. He has probably 

 attained no one of these conceptions in such a way as to 

 react definitely upon it. He acts in each case separately, 

 and simply because he cannot help it ; being so framed that 

 when that particular running thing called a mouse appears 

 in his field of vision he must pursue; that when that 

 particular barking and obstreperous thing called a dog 

 appears there, he must retire if at a distance, and scratch if 

 close by ; that he must withdraw his feet from water and his 

 face from flame, etc. His nervous system is to a great 



1 It is very doubtful whether the parental impulse is really inborn, 

 in the male human being. (See 442.) But this only demonstrates 

 how extremely difficult it is to distinguish an instinct from an acquired 

 desire, and, therefore, what a perfect substitute the latter is for instinct. 



