EVOLUTION DEFINED 9 



chance or whim. Whatever occurs coines as tlie resultant of 

 moving forces. Could we know and estimate these forces, we 

 should have, so far as our estimate is accurate and our logic 

 perfect, the gift of prophecy. Knowing the law, and knowing 

 the facts, we should foretell tlie results. To be ahle in some 

 degree to do this is the art of hfe. It is the ultimate end of 

 science, v/hich finds its final purpose in human conduct. 



"A law," according to Darwin, "is the ascertained se(iuencc 

 of events. '^ The actual sequence of events it is, in fact, but 

 man knows notliing of what is necessary, only of what has been 

 ascertained to occur. Because human observation and logic 

 can be only partial no law of life can be fully stated. Ht-cau.se 

 the processes of human mind are human, with organic limita- 

 tions, the study of the mind itself becomes a part of the science 

 of bionomics. For it is itself an instrument or a combination 

 of instruments by v/hich we acquire such knowledge of the 

 world outside of ourselves as may be needed in the art of living, 

 in the degree in which we are able to practice that art. 



The necessary sequence of events exists, whether we are able 

 to comprehend it or not. The fall of a leaf follows fixed laws 

 as surely as the motion of a planet. It falls by chance because 

 its short movement gives us no time for observation and calcu- 

 lation. It falls by chance because, its results being imini- 

 portant to us, we give no heed to the details of its motion. But 

 as the hairs of our head are all numbered, so are nunil)ored all 

 the g^Tations and undulations of every chance autumn leaf. 

 All processes in the universe are alike natural. The creation 

 of man or the growth of a state is as natural as the formation 

 of an apple or the growth of a snowbank. All are alike super- 

 natural, for they all rest on the huge unseen solidity of the 

 universe, the imperishability of matter, the conservation of 

 energy, and the immanence of law\ 



We sometimes classify sciences as exact antl inexact, m 

 accordance with our al^ility exactly to weigh forces and results. 

 The exact sciences deal with simple data accessible and (apable 

 of measurement. The results of their interactions can l)e 

 reduced to mathematics. Because of their essential simj>licity, 

 the mathematical sciences have been carrieil to great com- 

 parative perfection. It is easier to weigh an invisible planet 

 than to measure the force of heredity in a grain of corn. The 

 sciences of life are inexact because the human mind can never 



