SCIENTIFIC METHOD 75 



him a Kepler or a Galilei, sets to work on these 

 raw materials, and sifts from them their essence. 

 She bursts into full daylight only when a Newton 

 extracts the quintessence. There has been, as 

 yet, but one Newton; there have not been very 

 many Keplers." 



THE SCIENTIFIC USE OF THE IMAGINATION. 

 This was the title of a famous lecture in which 

 Tyndall discussed with eloquence and insight the 

 function of imagination in scientific research, 

 " Bounded and conditioned byco-operant reason," 

 he said, "imagination becomes the mightiest in- 

 strument of the physical discoverer." "There is 

 in the human intellect a power of expansion, I 

 might almost call it a power of creation, which is 

 brought into play by simple brooding over facts, 

 'the spirit brooding over chaos.' " 



It may be that the imaginative brooding sug- 

 gests a solution in some way that we do not at 

 present understand life is essentially creative; 

 it may be that there is a more or less unconscious 

 cerebral experimenting; it is certain that letting 

 the mind play among facts has often led to 

 magnificent conclusions. It seems that the solu- 

 tion is often reached first and the proof supplied 

 afterwards. Newton spoke of reaching his dis- 

 coveries "by attending my mind thereunto," 

 but it would be extremely interesting to know 

 more precisely what he meant. The steps by 



