SECTION 13. - GENERALISA TION OR EXTENSION. 99 



A generalisation, until proved, is an hypothesis which asserts 

 that what holds true of one fact holds true beyond that one 

 fact 1 For ordinary purposes the generalising process may be 

 supposed to succeed necessarily the preliminary process of 

 observation, since unclassified facts are scientifically of minimal 

 value. 



In defence of the syllogism it has been urged that in all 

 reasoning we assume some general fact, and that an individual 

 fact only exists as a member of a class. In conformity with 

 this it has been argued that the universal and not the particular 

 is real, and that the class precedes the particulars it com- 

 prehends. Let us, then, examine what signification is to be 

 attached to the term "General".' 2 



In the special example cited to illustrate the origin of hypo- 

 theses we only pre-supposed reasoning from one particular to 

 one other. I reflected: On my former visit my literary friend 

 stowed away a manuscript in a capacious envelope, therefore 

 his picking up a capacious envelope on my present visit is, 

 on general grounds of experience, to be interpreted similarly. 

 Particulars agreeing, likeness was posited. In my mind there 

 need not have been lurking any generalisation to the effect 

 that whenever any one seizes an unusually large envelope, he 

 wishes to stowe away a manuscript; or, what was true of the 



possible formulation of the world of facts, and in these attempts lie defined 

 the object, motive and method of science. Apart from the process of 

 economisation, therefore, science, with all its implications, has no meaning; 

 and, for the same reason, every truth, every statement, and every generali- 

 sation, owes its existence solely to the process of economisation." (G. Spiller, 

 Mind of Man, 1902, p. 121.) This implies that science does not deal as a 

 rule with any whole, for such a whole is generally an intricate complex 

 and is, besides, related to the totality of things, rendering it impossible in 

 our day to make concerning it any intelligible statement. However, since 

 the very meaning of a whole is also a mental product, it is unjustifiable 

 to speak of science as not treating of reality because of the present limita- 

 tions of its scope. Moreover, since the sciences differ in the inclusion of 

 constituent parts as much as pure mathematics does from physiography, it 

 is unprofitable to set up artificial divisions between the subject-matter of 

 science and that of common thought. The latter, indeed, is frequently more 

 abstract than a train of scientific cogitations. 



1 Generalisation is "the act of comprehending under a common name 

 several objects agreeing in some point which we abstract from each of them, 

 and which that common name serves to indicate". (Whately, Logic, p. 344.) 



"The extension of the concurrence from the observed to the unobserved 

 cases" is alone generalising. (Bain, Logic, vol. 2, p. 2.) 



"Generalisation consists in passing from observed phenomena to their 

 essential and invariable conditions; in the detection, as Jevons puts it, 

 of a true 'common nature'." (Welton, Manual of Logic, p. 193.) 



2 Sigwart says: "The number of instances from which a universal pro- 

 position is obtained makes no fundamental difference in the logical process 

 involved, and the character -of the process is obscured when the colligation 

 of a number of similar instances is put forward as its essential feature." 

 (Logic, vol. 2, p. 310.) Boeanquet (Logic, vol. 2, pp. 177-179) argues along 

 the same line. A sharp distinction needs to be drawn here between formal 

 logic and practical methodology. 



