THE FUNDAMENTAL PHYSIOLOGICAL ACTIONS 27 



race. So long as the good of the individual does not run counter, 

 to that of the race the individual is conserved, but as soon as the 

 good of the individual is opposed to that of the race the individual 

 is sacrificed. Thus in a state of nature the old and feeble suffer 

 destruction because their usefulness to the race is over, and they 

 are consuming food which may be required by the young and 

 vigorous. The elaborate humanitarian measures by which civi- 

 lized men attempt to prevent the destruction of the old, the 

 feeble, and the sick may seem, at first thought, absolutely opposed 

 to the purposes of nature, and so, perhaps, from a purely physical 

 standpoint they are, but when we recall that the really worth 

 while part of Man's life is intellectual and spiritual rather than 

 physical, and consider the influence of humanitarianism upon 

 this part, we realize that humanitarianism represents, after all, 

 one phase of the highest development of the purpose of Nature 

 with respect to Man. 



The Physiological Properties of organisms are the means by 

 which they are enabled to carry out the purpose of Nature with re- 

 gard to themselves. These properties are peculiarly fitted to 

 enable organisms to maintain themselves and their race upon 

 earth. Consider, for example, the usefulness of the functions of 

 movement, sensation, and co-ordination. The power of motion 

 is of great advantage to an animal, but only in connection with 

 sensation and co-ordination. The chief usefulness of motion to 

 the organism is the securing of food and the avoidance of harm. 

 Neither of these ends is served by aimless motion. To secure 

 food or to avoid harm the organism must have knowledge of its 

 environment. This is gained through the operation of the prop- 

 erty of sensation. The mere possession of knowledge is of no 

 avail unless the movements can be directed in accordance with it. 

 For this guidance the property of co-ordination serves. 



Only through the successful co-operation of these three physio- 

 logical properties is the organism able to adapt itself to its environ- 

 ment and so to live. Continued survival requires the continuous 

 co-operation of these functions. The definition sometimes heard of 

 life as continuous adaptation emphasizes this truth. 



The function of assimilation and those phases of dissimilation 

 not immediately concerned with the properties of motion, sensa- 

 tion, and co-ordination are, nevertheless, essential to the life of 



