208 DOCTRINE OF EVOLUTION 



for assuming an identical form of knowledge as a pos- 

 session of these insects. Many investigators have 

 dealt with these fascinating subjects, and they are al- 

 most unanimous in the conclusion that the instinct 

 of an insect is a mechanical and hereditary synthesis 

 of combined reflex acts. 



The lower orders of psychological processes play a far 

 larger part in the lives of the higher animals than we are 

 wont to believe. A pointer and sheep dog possess 

 different qualifications in the way of instincts that 

 make them useful to man in different ways. A bull- 

 dog or a game-cock does not reason out its course of 

 action during a contest, but like a mechanism when 

 the spring is released, it acts promptly and with effect. 

 A ball flashing past the human eye causes the lids to 

 close unconsciously, and it is not always possible to 

 inhibit this instinctive mechanical act by the exercise 

 of the will. An examination of the workings of the 

 human body reveals manifold activities of an even lower 

 or reflex nature, like the movements of the viscera and 

 the adjustments in respect to the amount of supplies 

 of blood sent to different parts of the body as local 

 needs arise. Directed always by specific portions of 

 the nervous system, such reflex actions play their part 

 in human life without any effort on the part of reason 

 and so-called will, and without coming into conscious- 

 ness except indirectly and subsequently. 



Passing by many interesting members of the psy- 

 chological series of intergrading forms, we reach the 

 familiar animals like the cat and dog and horse which 

 display what is called intelligence. This is the power 

 to learn by experience, and to improve the quality and 



