TERMINOLOGY AND NOMENCLATURE. 431 



cess, as is umloubtedly the case in algebra. But, if we except c;eom- 

 etry, the cDiichisioiis ofvvliich are ah-eaily as certain anil' exact as tliey 

 can be made, tliere is no si'Ience but that of number, in wliicli tht; prac- 

 ticiU vaUcUty of a reasoning can be apparent to any persrtn who has 

 looked only at the form of the process. Whoever has assented to all 

 that was said in the last Book concerning the case of the Composition 

 of Causes, and the still stronger case of the entire supersession of one 

 set of laws by another, is aware that geometry and algebra are the 

 only sciences of which the propositions arc categorically true : the 

 general propositions of all other sciences are true only hypothetically, 

 sifj>j>os//ig that no counteracting cause happens to interfere. A con- 

 clusion, therefore, however correctly deduced, in point of form, from 

 admitted laws of nature, will have no other than a hypothetical cer- 

 tainty. At every step we must assure ourselves that no other law of 

 nature has superseded, oi-*!nterminglcd its operation with, those which 

 are the premisses of the reasoning; and how can this be done by 

 merely looking at the words ] We must not only be constantly think- 

 ing of the phenomena themselves, but we must be constantly looking 

 at them; making ourselves acquainted with the peculiarities of every 

 case to which we attempt to apply our general principles. 



The algebraic notation, viewed as a philosophical language, is per- 

 fect in its adaptation to the subjects for which it is commonly employed, 

 namely those of which the investigations have already been reduced 

 to the ascertainment of a relation between numbers. But, admirable 

 as it is for its own purpose, the properties by which it is rendered such 

 are so far from constituting it the ideal model of philosophical language 

 in general, that the more nearly the language of any other branch of 

 science approaches to it, the less fit that language is for its own proper 

 functions. On all other subjects, instead- of contrivances to prevent 

 our attention from being distracted by thinking of the meaning of our 

 signs, we require contrivances to make it impossible that we should 

 ever lose siglit of that meaning even for an instant. 



With this view, as much meaning as possible should be thrown into 

 the formation of the word itself; the aids of derivation and analogy 

 being made available to keep alive a consciousness of all that is signi- 

 fuid by it. In this respect those languages have an immense advantage 

 which form their compounds and derivatives from native roots, like 

 the (Terman, and not from those of a foreign or a dead language, as is 

 so much the case with English, French, and Italian : and the best are 

 those which foiTn them according to fixed analogies, corresponding to 

 the relations between the ideas to be expressed. All languages do 

 this more or less, but especially, among modem European languages, 

 the German : while even that is inferior to the Greek, in which the 

 relation between the meaning of a derivative word and that of its prim- 

 itive, is in general clearly marked by its mode of formation ; except in 

 the case of words compounded with prepositions, which, it nmst be 

 acknowledged, are often, in both those languages, extremely anomalous. 



But all that can be done, by the mode of constructing words, to 

 prevent them fi-om degenerating into sounds passing through the mind 

 without any distinct apprehension of what they signify, is far too little 

 for the necessity of the case. Words, however well constructed origi- 

 nally, are always tending, like coins, to have their inscription worn off 

 by passing from hand to hand; and the only possible mode of reviving 



