116 INDUCTION. 



The principle of elimination, that great logical instrument 

 which he had the immense merit of first bringing into general 

 use, he deemed applicable in the same sense, and in as un- 

 qualified a manner, to the investigation of the coexistences, 

 as to that of the successions of phenomena. He seems to have 

 thought that as every event has a cause, or invariable ante- 

 cedent, so every property of an object has an invariable co- 

 existent, which he called its Form : and the examples he 

 chiefly selected for the application and illustration of his 

 method, were inquiries into such Forms ; attempts to deter- 

 mine in what else all those objects resembled, which agreed 

 in some one general property, as hardness or softness, dry- 

 ness or moistness, heat or coldness. Such inquiries could 

 lead to no result. The objects seldom have any such circum- 

 stances in common. They usually agree in the one point 

 inquired into, and in nothing else. A great proportion of the 

 properties which, so far as we can conjecture, are the likeliest 

 to be really ultimate, would seem to be inherently properties 

 of many different Kinds of things, not allied in any other 

 respect. And as for the properties which, being effects of 

 causes, we are able to give some account of, they have generally 

 nothing to do with the ultimate resemblances or diversities in 

 the objects themselves, but depend on some outward circum- 

 stances, under the influence of which any objects whatever are 

 capable of manifesting those properties ; as is emphatically 

 the case with those favourite subjects of Bacon's scientific 

 inquiries, hotness and coldness ; as well as with hardness and 

 softness, solidity and fluidity, and many other conspicuous 

 qualities. 



In the absence, then, of any universal law of coexistence, 

 similar to the universal law of causation which regulates 

 sequence, we are thrown back upon the unscientific induction 

 of the ancients, per enumerationem simplicem, ubi non reperitur 

 instantia contradictoria. The reason we have for believing that 

 all crows are black, is simply that we have seen and heard of 

 many black crows, and never one of any other colour. It 

 remains to be considered how far this evidence can reach, and 

 how we are to measure its strength in any given case. 



