BIOLOGICAL INTRODUCTION 21 



choking up with white-weed. The boss will have to plow it up 

 next year and replant it." The extraordinary natural beauty 

 of the place is, however, unnoticed amid the round of daily 

 work and simple pleasure. 



The artist looks out upon the same scene, but through what 

 different eyes! The mass of white daisies and the rocky knoll 

 beyond ruddy with sheep sorrel suggest to him no waste of 

 valuable pasture land, but a harmony of color and grace of form 

 upon which he feasts his soul. The esthetic delights of the 

 forest, the sky, the brook, and the overhanging crag beyond are 

 for him unmixed with any utilitarian motive. 



Each of these four organisms occupies, in one sense, the 

 same environment; but it is evident that the factors of this 

 environment with which each comes into active vital relations 

 are immeasurably different. They correspond with or are at- 

 tuned to quite different energy complexes, though the cor- 

 respondence or interaction is very real in each case. This has 

 been stated very simply by Dr. Jennings when he says that 

 every species of organism has its characteristic "action system," 

 i. e., a habitual mode of reaction to its environment which is 

 determined wholly or in part by its inherited organization. 



Every animal and every plant has, accordingly, a definite 

 series of characteristic movements which it can make in re- 

 sponse to external stimulation. This is all that Jennings means 

 by the "action system." We humans are no exception to this 

 rule of life. We move along in a more or less stereotyped way, 

 through more or less familiar grooves, in our daily work. 

 Much of this work is routine, done about as mechanically as 

 the flower unfolds its petals to the morning sun or the honey- 

 bee gathers in her store of honey. This is our action system. 

 Of course, we have much else to do besides this routine, and our 

 actual value to the community is in large measure determined by 

 our ability to vary this routine in adaptation to new situations 

 as they arise. Even the daisy has a little of this capacity for 

 independently variable action; the insect has more; and man's 

 preeminence in the world is due primarily to his larger powers 

 of adapting his reactions not only to the needs of the moment, 

 but to probable future contingencies, i. e., of varying his 

 inborn action system by intelligently directed choices. 



