42 INTRODUCTION 



thinkers. The complaint is often made that science 

 speculates too much. It is quite the other way. 

 One has only to read the average book of science 

 in almost any department to wonder at the wealth 

 of knowledge, the brilliancy of observation, and the 

 barrenness of idea. On the other hand, though 

 scientific experts will not think themselves, there is 

 always a multitude of onlookers waiting to do it 

 for them. Among these what strikes one is the 

 ignorance of fact and the audacity of the idea. The 

 moment any great half-truth in Nature is unearthed, 

 these unqualified practitioners leap to a generaliza- 

 tion ; and the observers meantime, on the track of 

 the other half, are too busy or too oblivious to 

 refute their heresies. Hence, long after its founda- 

 tions are undermined, a brilliant generalization will 

 retain its hold upon the popular mind ; and 

 before the complementary, the qualifying, or the 

 neutralizing facts can be supplied, the mischief is 

 done. 



But while this is true of many who play with 

 the double-edged tools of science, it is not true of 

 a third class. When we turn to the pages of the 

 few whose science is adequate and whose sweep 

 IS over the whole vast horizon, we find, as we 

 should expect, some recognition of the altruistic 

 factor. Though Mr. Herbert Spencer, to whom 



I 



