SCIENTIFIC HYPOTHESIS 255 



No one would deny the right of forming a provi- 

 sional assumption to the intelligence officer interpret- 

 ing a cipher, or to the detective unravelling the mys- 

 tery of a crime. The first assumes that the message 

 is in a certain language, and, perhaps, that each sym- 

 bol employed is the equivalent of a letter , his assump- 

 tion is put to the proof of getting a reasonable and 

 consistent meaning from the cipher. The detective 

 assumes a motive for the crime, or the employment 

 of certain means of escape ; even if his assumption 

 does not clear up the mystery, it may have value as 

 leading to a new and more adequate assumption. 



Henri Poincare has pointed out that one of the 

 most dangerous forms of hypothesis is the uncon- 

 scious hypothesis. It is difficult to prove or disprove 

 because it does not come to clear statement. The al- 

 leged devotee of facts and of things as they are, in 

 opposing the assumptions of an up-to-date science, is 

 often, unknown to himself, standing on a platform 

 of outworn theory, or of mere vulgar assumption. 

 For example, when Napoleon was trying to destroy 

 the commercial wealth of England at the beginning 

 of the nineteenth century, he unconsciously based his 

 procedure on an antiquated doctrine of political 

 economy. For him the teachings of Adam Smith and 

 Turgot were idle sophistries. " I seek," he said to 

 his Minister of Finance, "the good that is prac- 

 tical, not the ideal best : the world is very old , we 

 must profit by its experience; it teaches that old 

 practices are worth more than new theories : you are 

 not the only one who knows trade secrets." We are 

 not here especially concerned with the question of 

 whether Napoleon was or was not pursuing the best 



