226 INDUCTION. 



are compelled by the constitution of our thinking faculty to assume as true. 

 Having so recently, and at so much length, combated a similar doctrine as 

 applied to the axioms of mathematics, by arguments which are in a great 

 measure applicable to the present case, I shall defer the more particular 

 discussion of this controverted point in regard to the fundamental axiom 

 of induction, until a more advanced period of our inquiry.* At present it 

 is of more importance to understand thoroughly the import of the axiom 

 itself. For the proposition, that the course of nature is uniform, possesses 

 rather the brevity suitable to popular, than the precision requisite in phil- 

 osophical language : its terms require to be explained, and a stricter than 

 their ordinary signification given to them, before the truth of the assertion 

 can be admitted. 



§ 2. Every person's consciousness assures him that he does not always 

 expect uniformity in the course of events; he does not always believe that 

 the unknown will be similar to the known, that the future will resemble the 

 past. Nobody believes that the succession of rain and fine weather will bo 

 the same in every future year as in the present. Nobody expects to have 

 the same dreams repeated every night. On the contrary, every body men- 

 tions it as something extraordinary, if the course of nature is constant, and 

 resembles itself, in these particulars. To look for constancy where con- 

 stancy is not to be expected, as for instance that a day which has once 

 brought good fortune will always be a fortunate day, is justly accounted 

 superstition. 



The course of nature, in truth, is not only uniform, it is also infinitely va- 

 rious. Some phenomena are always seen to recur in the very same combi- 

 nations in which we met with them at first ; others seem altogether capri- 

 cious; while some, which we had been accustomed to regard as bound 

 down exclusively to a particular set of combinations, we unexpectedly find 

 detached from some of the elements with which we had hitherto found 

 them conjoined, and united to others of quite a contrary description. To 

 an inhabitant of Central Africa, fifty years ago, no fact probably appeared 

 to rest on more uniform experience than this, that all human beings are 

 black. To Europeans, not many years ago, the proposition. All swans are 

 white, appeared an equally unequivocal instance of uniformity in the course 

 of nature. Further experience has proved to both that they were mistaken; 

 but they had to wait fifty centuries for this experience. During that long 

 time, mankind believed in a uniformity of the course of nature where no 

 such uniformity really existed. 



According to the notion which the ancients entertained of induction, the 

 foregoing were cases of as legitimate inference as any inductions whatever. 

 In these two instances, in which, the conclusion being false, the ground of 

 inference must have been insufficient, there was, nevertheless, as much 

 ground for it as this conception of induction admitted of. The induction 

 of the ancients has been well described by Bacon, under the name of "In- 

 ductio per enumerationem simplicem, ubi non reperitur instantia contradic- 

 toria." It consists in ascribing the character of general truths to all prop- 

 ositions which are true in every instance that we happen to know of. This 

 is the kind of induction which is natural to the mind when unaccustomed 

 to scientific methods. The tendency, which some call an instinct, and 

 which others account for by association, to infer the future from the past, 



* Infra, chap, xxi. 



