Working Hypotheses. 225 



grains of sand on the sea-shore ; they might weigh 

 each one, and measure each one, and go on collecting 

 such facts until libraries were filled, and the minds 

 of men buried under their weight, and no addition 

 would be made to philosophy thereby. There must 

 be some method of selecting, some method of de- 

 termining what facts are valuable and what facts are 

 trivial. The fool collects facts ; the wise man selects 

 them. 



Amid the multiplicity of facts in the universe, how 

 does the wise man choose for his use ? The true 

 scientific man walks not at random through the 

 world, making notes of what he sees ; he chooses 

 some narrow field of investigation. Within this field 

 he reviews what is already known, and becomes con- 

 versant with the conclusions already reached. He 

 then seeks to discern more facts in this field, and to 

 make more careful discriminations therein, and then 

 to make more homologic classifications ; and, finally, 

 more thoroughly to discover the complexity of 

 sequences. 



If he attain to success in doing all this his investi- 

 gations are always suggested by some hypothesis 

 some supposition of what he may discover. He may 

 find that his hypothesis* is wrong, and discover some- 

 thing else ; but without an hypothesis he discovers 

 nothing. A scientific man taking up a subject re- 

 views the facts that are known, and imagines that they 

 lead to conclusions that have not yet been reached 

 by others. His imagination may lead him quite 

 astray, yet he follows it, and says : " Now if this be 

 true, then there must be certain yet undiscovered 

 15 



