20 INDUCTION. 



the simplest phenomena, " if we did not often com- 

 mence by anticipating on the results ; by making a 

 provisional supposition, at first essentially conjectural, 

 as to some of the very notions which constitute the 

 final object of the inquiry*." Let any one watch the 

 manner in which he himself unravels any complicated 

 mass of evidence ; let him observe how, for instance, 

 he elicits the true history of any occurrence from the 

 involved statements of one or of many witnesses : he 

 will find that he does not take all the items of evi- 

 dence into his mind at once, and attempt to weave 

 them together : the human faculties are not equal to 

 such an undertaking : he extemporises, from a few of 

 the particulars, a first rude theory of the mode in 

 which the facts took place, and then looks at the other 

 statements one by one, to try whether they can be 

 reconciled with that provisional theory, or what cor- 

 rections or additions it requires to make it square with 

 them. In this way, which, as M. Comte remarks, 

 has some resemblance to the Methods of Approxima- 

 tion of mathematicians, we arrive, by means of hypo- 

 theses, at conclusions not hypothetical f. 



* Cours de Philosophic Positive, ii., 434. 



t As an example of a legitimate hypothesis according to the 

 test here laid down, M. Comte cites that of Broussais, who, pro- 

 ceeding on the very rational principle that every disease must 

 originate in some definite part or other of the organism, boldly 

 assumed that certain fevers, which not being known to be local 

 were called constitutional, had their origin in the mucous membrane 

 of the alimentary canal. The supposition was indeed, as there is 

 strong ground to believe, erroneous ; but he was justified in making 

 it, since by deducing the consequences of the supposition, and com- 

 paring them with the facts of those maladies, he might be certain of 

 disproving his hypothesis in case it was ill founded, and might 

 expect that the comparison would materially aid him in framing 

 another more conformable to the phenomena. 



The doctrine, now universally received, that the earth is a great 



