CHAPTER II.* 



THE ORIGIN OF LIFE. 

 What is Life ? 



IN taking up the study of the history of life, we 

 must first ask the question: what is life? This 

 question is asked not in expectation that any satis- 

 factory answer is possible, but in order that we may 

 get as clearly as possible before our minds the chief 

 facts in modern thought concerning the subject. It 

 is clearly true that our scientists have by their specu- 

 lations and experiments so completely changed our 

 ideas of life that it sometimes seems as if we could 

 almost grasp the real essence of the matter. The 

 solution of the life question is said to be close at 

 hand. Tt is well for us at the outset, then, to review 

 the question, to see where we stand to-day in our 

 knowledge of life, and to notice what pointy have 

 been settled and what points still baffle comprehen- 

 sion. For, thus far, this life essence has been an 

 ignis fatuus ; and although many preliminary ques- 

 tions have been solved in pursuit of it, their solutions 



* The substance of this chapter was originally published in the 

 New Princeton Review. 



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