66 Dr. WHEWELL'S CRITICISM OF ARISTOTLE'S ACCOUNT OF INDUCTION. 



false proposition ; and even if the analysis were now made conformable to our present knowledge, 

 that induction, analysed as above, would still involve a proposition which to-morrow may shew 

 to be false. But yet no one, I suppose, doubts that Kepler's discovery was really a discovery 



the establishment of a scientific truth on solid grounds; or, that it is a scientific truth for 



us, notwithstanding that we are constantly discovering new planets. Therefore the syllogistic 

 analysis of it now discussed (namely, that which introduces simple enumeration as a step) is 

 not the right analysis, and does not represent the grounds of the Inductive Truth, that all the 

 planets describe ellipses. 



It may be said that all the planets discovered since Kepler's time conform to his law, and 

 thus confirm his discovery. This we grant : but they only confirm the discovery, they do not 

 make it ; they are not its ground work. It was a discovery before these new cases were known ; 

 it was an inductive truth without them. Still, an objector might urge, if any one of these new 

 planets had contradicted the law, it would have overturned the discovery. But this is too 

 boldly said. A discovery which is so precise, so complex (in the phenomena which it explains) 

 so supported by innumerable observations extending through space and time, is not so easily over- 

 turned. If we find that Uranus, or that Encke's comet, deviates from Kepler's and Newton's 

 laws, we do not infer that these laws must be false ; we say that there must be some disturbing 

 cause in these cases. We seek, and we find these disturbing causes : in the case of Uranus, 

 a new planet ; in the case of Encke's comet, a resisting medium. Even in this case therefore, 

 though the number of particulars is limited, the Induction was not made by a simple enume- 

 ration of all the particulars. It was made from a few cases, and when the law was discerned 

 to be true in these, it was extended to all ; the conversion and assumed universality of the pro- 

 position that " these are planets," giving us the proposition which we need for the syllogistic 

 exhibition of Induction, "all the planets are as these." 



I venture to say further, that it is plain, that Aristotle did not regard Induction as the 

 result of simple enumeration. This is plain, in the first place, from his example. Any pro- 

 position with regard to a special class of animals, cannot be proved by simple enumeration : for 

 the number of particular cases, that is, of animal species in the class, is indefinite at any period 

 of zoological discovery, and must be regarded as infinite. In the next place, Aristotle says 

 (fi 10 of the above extract) "We must conceive that C consists of a collection of all the particular 

 cases: for induction is applied to all the cases." We must conceive (voe7v) that C in the major, 

 consists of all the cases, in order that the conclusion may be true of all the cases ; but we can- 

 not observe all the cases. But the evident proof that Aristotle does not contemplate in this 

 chapter an Induction by simple enumeration, is the contrast in which he places Induction and 

 Syllogism. For Induction by simple enumeration stands in no contrast to Syllogism. The 

 Syllogism of such Induction is quite logical and conclusive. But Induction from a compara- 

 tively small number of particular cases to a general law, does stand in opposition to Syllogism. 

 It gives us a truth, — a truth which, as Aristotle says, (fi 14) is more luminous than a truth 

 proved syllogistically, though Syllogism may be more natural and usual. It gives us (& 11) 

 immediate propositions, obtained directly from observation, and not by a chain of reasoning: 

 "first truths," the principles from which syllogistic reasonings maybe deduced. The Syllogism 

 proves by means of a middle term (§13) that the extreme is true of a third thing: thus 

 (avholous being the middle term) 



