THE BREATH OF LIFE 



terms merely descriptive of chemical and physical 

 phenomena ever can. Life is a motion in matter, 

 but of another order from that of the physico-chem- 

 ical, though inseparable from it. We may forego the 

 convenient term "vital force." Modern science 

 shies at the term "force." We must have force or 

 energy or pressure of some kind to lift dead matter 

 up into the myriad forms of life, though in the last 

 analysis of it it may all date from the sun. When it 

 builds a living body, we call it a vital force; when 

 it builds a gravel-bank, or moves a glacier, we call 

 it a mechanical force; when it writes a poem or com- 

 poses a symphony, we call it a psychic force — all 

 distinctions which we cannot well dispense with, 

 though of the ultimate reality for which these terms 

 stand we can know little. In the latest science heat 

 and light are not substances, though electricity is. 

 They are peculiar motions in matter which give rise 

 to sensations in certain living bodies that we name 

 light and heat, as another peculiar motion in mat- 

 ter gives rise to a sensation we call sound. Life is 

 another kind of motion in certain aggregates of 

 matter — more mysterious or inexplicable than all 

 others because it cannot be described in terms of the 

 others, and because it defies the art and science of 

 man to reproduce. 



Though the concepts "vital force" and "life 

 principle" have no standing in the court of modern 

 biological science, it is interesting to observe how 



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