Kidd. — What is Science? lxi 



of nature; and the analysis, deduction, and induction, of the mental 

 operations cannot be reasonably or consistently omitted from a classification of 

 the sciences. I repeat, however, that the omission would not, in my opinion, 

 alter the due definition of Science. 



Natural History also, in its various branches, is now almost unanimously 

 designated as Science, In short, we find that, with a near approach to 

 unanimity, this appellation is given to Pure Mathematics, to Logic, to Natural 

 Philosophy or Physics, to Natural History, to Psychology, to Ethics, to 

 Political Economy, and whatever others. Max Miiller names the department 

 of investigation in which he occupies a place so distinguished " the Science of 

 Language "; and he even proposes to construct a " Science of Religion." We 

 hear also occasionally about the science of history or of historical criticism. 

 Such is the wide range of the appellation Science ; and our question is, Has 

 this term, in all its recognized applications, a common connotation, and if so, 



what is it ? 



This question does not require our engaging in any elaborate classification 

 of the sciences, or reviewing the classifications that have been made ; but, for 

 the purpose of our inquiry, there is one obvious distinction requisite to be 

 applied, viz., that between the Demonstrative or Abstract Sciences and those 

 which are Inductive or Experimental. To the former class belong the 

 sciences of Pure Mathematics, and also Formal Logic. Like the applied 

 mathematics, Logic may also be, and is, treated as inductive. The necessary 

 sequence of the logical formulae from self-evident principles is unquestionable ; 

 but it is a further inquiry, how far the actual phenomena of the human mind 

 are represented by those formulae. Something of the same kind presents 

 itself in Mechanical Science. The fundamental proposition of the composition 

 of forces, called the Parallelogram of Forces, is deducible from principles that 

 may be accepted as self-evident ; and multitudes of results are derived from 

 that proposition with the aid of pure mathematics ; but yet it is usual and 

 right, in treatises on Statics and Dynamics, to adduce the specific testimony 

 of experience. 



Every portion of science, then, is either demonstrative or inductive, or both. 

 By u demonstrative " I mean, deduced by necessary sequence from self-evident 

 principles ; while an inductive result is, of course, a finding of experience. 

 Now, of the definitions of Science that I have met with, each is applicable 

 either exclusively to Demonstrative Science, or exclusively to that which is 

 Experiential The definition given in the Encyclopedia Britannica, the eighth 

 or last edition, is perhaps an exception. It is as follows: — "Science, in its 

 strictest sense, is a body of organized knowledge, whose phenomena are 

 arranged so as to exhibit the reasons or causes by which they are influenced 

 in their legitimate connection and interdependence." To this definition there 



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