CH. xi.] PHILOSOPHY OF INDUCTIVE INFERENCE. 219 



attempt to show that inference, whether inductive or 

 deductive, is never more than an unfolding of the contents 

 of our experience, and that it always proceeds upon the 

 assumption that the future and the unperceived will be 

 governed by the same conditions as the past and the 

 perceived, an assumption which will often prove to be 

 mistaken. 



In inductive as in deductive reasoning the conclusion 

 never passes beyond the premises. Eeasoning adds no 

 more to the implicit contents of our knowledge, than the 

 arrangement of the specimens in a museum adds to the 

 number of those specimens. Arrangement adds to our 

 knowledge in a certain sense : it allows us to perceive the 

 similarities and peculiarities of the specimens, and on the 

 assumption that the museum is an adequate representation 

 of nature, it enables us to judge of the prevailing forms of 

 natural objects. Bacon's first aphorism holds perfectly 

 true, that man knows nothing but what he has observed, 

 provided that we include his whole sources of experience, 

 and the whole implicit contents of his knowledge. In- 

 ference but unfolds the hidden meaning of our observations, 

 and the theory of probability shows how far we go beyond 

 mir data in assuming that new specimens will resemble the 

 old ones, or that the future may be regarded as proceeding 

 uniformly with the past. 



Various Classes of Inductive Truths. 



It will be desirable, in the first place, to distinguish 

 between the several kinds of truths which we endeavour 

 to establish by induction. Although there is a certain 

 common and universal element in all our processes of 

 reasoning, yet diversity arises in their application. 

 Similarity of condition between the events from which 

 we argue, and those to which we argue, must always be 

 the ground of inference ; but this similarity may have 

 regard either to time or place, or the simple logical 

 combination of events, or to any conceivable junction of 

 circumstances involving quality, time, and place. Having 

 met with many pieces of substance possessing ductility 

 and a bright yellow colour, and having discovered, by 

 perfect induction, that they all possess a high specific 



