THE DISPLAY OF ENERGY :56r> 



photoreceptive organs, while differences in temperature might affect 

 many different groups of tissues or organs in different ways 



Another view, quite opposite to this, is the organismal theory. 

 Here the unity of the organism as an interacting whole is stressed. It 

 is considered as an individual and not as a collection of cells and tis- 

 sues. The study of embryology bears out this idea, for in the develop- 

 ment of the egg certain regions of protoplasm, instead of certain cells, 

 develop into the future embryo. The egg at an early stage shows 

 polarity, a right and left side as well as an anterior and posterior end 

 of the future organism, some time before it divides into cells. Profes- 

 sor Child of the University of Chicago has developed and tested a 

 theory of the unity of the (organism which he calls the axial gradient 

 theory that helps in understanding the complex response patterns ob- 

 served in the higher forms of life. He considers an animal as having 

 definite axes of polarity, or symmetry, the anterior end containing 

 the most sensitive recei^•ing structures. Since the brain is the most 

 active protoplasmic substance its metabolic rate is higher than that 

 of the rest of the organism, while its activity controls other parts of 

 the organism. 



This concept of the organism is an aid to a better understanding of 

 the complicated reactions and responses that are found in higher 

 animals. It is difficult to explain the complex response patterns of 

 vertebrates unless they are considered to be organized masses of proto- 

 plasm which respond as units to the total pattern of stimuli rather 

 than to individual stimuli. Living animals, at least those high in the 

 scale of life, respond to total situations rather than to isolated stimuli. 

 Such a point of view is taken by the "Gestalt " group of psychologists, 

 who use the term insight to describe an organized response at the con- 

 scious behavior level. Such a response can be shown to be directed 

 toward a goal, the complex movements being organized in relation to 

 that goal, the result of which is that the animal is able to solve its life 

 problems. According to this theory, a child who is learning to walk 

 does not make random "trial and error" movements. The uncer- 

 tainty of its first steps is due to a lack of maturity of the muscles and 

 of the nervous system, and not to the lack of a goal. This can be seen 

 in a comparison of two children of the same age, one of whom is 

 allowed to walk early, the other who has been kept off its feet for fear 

 of having the legs bowed. The latter will walk almost at once when 

 allowed to try the new "stunt." When maturity of muscles and 

 nerves is attained it becomes possible for a total behavior pattern to 



