The Logic of Evohitioii 



cannot even imagine the power which they will 

 bestow or the height to which they will raise us. 



We cannot fail to notice that we have here a 

 succession of motives of increasing power. Fear 

 usually overcomes appetite; but anger, and much 

 more, parental affection, overcomes fear. But 

 even this emotion is of less efficiency than human 

 maternal love where the feeling of loyalty and 

 duty mingles with maternal affection. The 

 lower motives may blaze out fiercely, but always 

 more or less fitfully, the higher move toward a 

 steady purpose befitting human powers and life. 



The lower motives are easily satisfied, and 

 often perish with the using. We remember our 

 childish anticipations of the holiday dinner, and 

 our disappointment because appetite failed be- 

 fore the arrival of the delicacies which we had 

 most anticipated. And over-indulgence was fol- 

 lowed by penitential fasting. 



But the higher motives grow with every satis- 

 faction of their cravings. The artist forgets 

 cold and hunger in the joy of his creative work. 

 Higher forms of beauty continually lure him to 

 greater efforts. Professor Huxley used to say 

 that the passion for original investigation was 

 harder to break than the craving for intoxicating 



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