CHANCE, AND ITS ELIMINATION. 53 



there be any connexion between rain and any particular wind. 

 Bain, we know, occasionally occurs with every wind ; there 

 fore the connexion, if it exists, cannot be an actual law; but 

 still, rain may be connected with some particular wind through 

 causation ; that is, though they cannot be always effects of the 

 same cause (for if so they would regularly coexist), there may 

 be some causes common to the two, so that in so far as either 

 is produced by those common causes, they will, from the laws 

 of the causes, be found to coexist. How, then, shall we ascer 

 tain this ? The obvious answer is, by observing whether rain 

 occurs with one wind more frequently than with any other. 

 That, however, is not enough ; for perhaps that one wind 

 blows more frequently than any other ; so that its blowing 

 more frequently in rainy weather is no more than would 

 happen, although it had no connexion with the causes of rain, 

 provided it were not connected with causes adverse to rain. In 

 England, westerly winds blow during about twice as great a 

 portion of the year as easterly. If, therefore, it rains only 

 twice as often with a westerly, as with an easterly wind, we 

 have no reason to infer that any law of nature is concerned in 

 the coincidence. If it rains more than twice as often, we may 

 be sure that some law is concerned ; either there is some cause 

 in nature which, in this climate, tends to produce both rain 

 and a westerly wind, or a westerly wind has itself some ten 

 dency to produce rain. But if it rains less than twice as often, 

 we may draw a directly opposite inference : the one, instead of 

 being a cause, or connected with causes, of the other, must be 

 connected with causes adverse to it, or with the absence of 

 some cause which produces it ; and though it may still rain 

 much oftener with a westerly wind than with an easterly, so 

 far would this be from proving any connexion between the 

 phenomena, that the connexion proved would be between rain 

 and an easterly wind, to which, in mere frequency of coinci 

 dence, it is less allied. 



Here, then, are two examples : in one, the greatest pos 

 sible frequency of coincidence, with no instance whatever to 

 the contrary, does not prove that there is any law ; in the 

 other, a much less frequency of coincidence, even when non- 



