Kibd. — Induction and Necessary Truth. xxxix 



the other Extreme (the Major) belongs to the Middle." By the Middle 

 Term, in the Aristotelian phraseology, is to be understood a certain Class of 

 things ; by the Major Extreme an Attribute ascribed, or to be ascribed, to 

 that class ; and by the Minor Extreme a Portion or Portions of the same 

 class. Induction, therefore, as explained by Aristotle, is this : the examining 

 the several portions of a given class of things ; the finding that they each 

 possess a certain attribute other than the attribute which constitutes the class ; 

 and the inferring that the observed attribute belongs to the members of that 

 class universally. The following, for example, would be an Aristotelian 

 induction : The capability of combining with oxygen is a property of iron, of 

 copper, of gold, of silver, of lead, of tin, etc. j and these constitute the whole 

 class Metal ; therefore, whatever is a metal has the property of combining 

 with oxygen. In another portion of Aristotle's works the following explana- 

 tion is given (Top. I. 12) : " Induction is the proceeding from the singulars to 

 the universal. U.g., let us suppose that the person who has knowledge is best 

 as a pilot, and as a charioteer ; and, universally, in each department the 

 person who has knowledge is the most excellent."* 



The only induction adequately analysed by the ancients was that in which 

 all the portions of the class, respecting which the inference is to be made, are 

 supposed to be known by direct experience. But in actual practice the data 

 of induction are of course very rarely capable of being thus exhaustive ; and 

 indeed the word Induction is now specially appropriated to what the old 

 logicians called Incomplete Induction, viz., that in which only a portion of the 

 class in question is experientially known, which portion is assumed to be a 

 sufficient specimen of the whole. 



The title, Father of Inductive Philosophy, has been frequently awarded to 

 Francis Bacon. The designation is not quite appropriate, nor yet altogether 

 unfitting. Bacon did not himself extend the domain of experimental science ; 

 he did not appreciate duly what some investigators of now illustrious renown 

 had a short time previously effected ; his exposition of the methods of investi- 

 gation was unavoidably indefinite, and it is now perceived to be, in certain 

 most important respects, essentially erroneous. What Bacon did was this : he 

 descried, he deeply felt, and with majestic eloquence he proclaimed and 

 enforced the principle that the great want of mankind in his age, as to science 

 and art, was the extensive observation and strict questioning of nature ; with 



* Some writers, including Archbishop Whately, assume that epagoge, or induction, in 

 the logical application, means properly the bringing in of the instances ; according to which 

 interpretation the correct phraseology would be, " induction of facts," and "inference 

 from induction," not induction from facts. This explanation is not in accordance with 

 the words of Aristotle and other ancient writers. Aristotle remarks ( Analyt. Pr. II. 23) 

 that "Induction is by moans of all " (epagoge dia panton), not Induction is of all 

 (epagoge panton). Again, he says, in words quoted above, " Induction" (not inference 

 from induction) " is the proceeding from the singulars to the universal (apo ton kath 

 hekaston epi ta katholon ephodos. ) The word inductio is used similarly. 



