310 



PART V. -WORKING STAGE. 



make discoveries. It was the power of never letting exceptions 

 pass unnoticed." (Charles Darwin, 1902, p. 94.) And his analyst 

 writes : "The starting points of his investigations were frequently 

 what seemed to other men interesting, but unimportant or in- 

 convenient, exceptional facts." (Frank Cramer, op. cit, p. 230.) 1 

 John Stuart Mill speaks in Chapter 4 of his Autobiography of 

 "a mental habit to which I attribute all that I have ever done, 

 or ever shall do, in speculation: that of never accepting half- 

 solutions of difficulties as complete ; never abandoning a puzzle, 

 but again and again returning to it until it was cleared up ; never 

 allowing obscure corners of a subject to remain unexplored, be- 

 cause they did not appear important ; never thinking that I per- 

 fectly understood any part of a subject until I understood the 

 whole". Of Lord Kelvin, his biographer says: "He believed 

 that light would come at last on the most baffling of problems, 

 if only it were looked at from every point of view and its con- 

 ditions were completely formulated." (Lord Kelvin, by Andrew 

 Gray, 1908, p. 306.) "It was a happy thought of Glauber", 

 writes Sir John Herschel, in his Discourse, "to examine what 

 everybody else threw away." (161.) "In case any exception 

 occurs, it must be carefully noted and set aside for re-examina- 

 tion at a more advanced period." (172.) "It is commonly stated", 

 writes Thorpe, "that the exception is a proof of the rule. The 

 history of science can show many instances whereby the rule 

 has been demolished by the exception. Little facts have killed 

 big theories, even as a pebble has slain a giant." (Op. cit., 

 vol. 1, p. 85.) Sir Michael Fyster, speaking of the scientific 

 worker, declares: "He must be alert of mind. Nature is ever 

 making signs to us, she is ever whispering to us the beginnings 

 of her secrets; the scientific man must be ever on the watch, 

 ready at once to lay hold of Nature's hint, however small, to 

 listen to her whisper, however low." (Presidential Address to 

 the British Association, 1899, p. 16.) 



We should, furthermore, be alert in our thought, utilising all the 

 serviceable memories and rapidly elaborating as many provisional 

 conclusions and deductions as the circumstances permit. 



Primarily we need to be guided by the consideration, illustrated 

 in Conclusion 19, that what obtrudes itself is most generally 

 indifferent scientifically, and that what is significant scientifically 

 has to be searched for in unsuspected quarters. Common ob- 

 servation would never have revealed to us the nature of the 

 white corpuscles or phagocytes which, according to Metschnikoff , 



1 Adverting to how Sir William Crookes was led to his vacuum tube 

 experiments, Sir William Ramsay (Essays Biographical and Chemical, 1908) 

 remarks: "Here again we see the advantage of following up small trails; 

 they may widen to great and most important roads." (P. 124.) And he adds : 

 believe that Ro'ntgen's discovery arose from an accidental observation 

 that a box of photographic plates left near a Crookes tube became 'fogged', 

 and he too had genius to follow up this clue." (P. 125.) Poincare has a 

 suggestive passage on this point in Science et methode, 1908, p. 311. 



