TERMINOLOGY AND NOMENCLATURE. 421 



because when confined to that particular meaning, it would no longer 

 have had the indistinctness which formed its recommendation. Many 

 terms, in many diHcrent languages, which originally had a more general 

 meaning, have been unfitted for other uses by acquiring this very con- 

 notation. And a vast variety of other words, without any relation to 

 that peculiar subject, have one after another fallen into disuse except 

 among the coarse and uncultivated, because tlicy had come to connote 

 too directly and unequivocally something which people did not like to 

 have brought very distinctly before their imagination. 



"Without any further multiplication of examples to illustrate the 

 changes which usage is continually making in the signification of terms, 

 I shall add, as a practical rule, that the logician, not being able to pre- 

 vent such transformations, should submit to them with a good grace 

 when they are iiTevocably effected, and if a definition is necessary, 

 define the word according to its new meaning ; retaining the former as 

 a second signification, if it is needed, and if there be any chance of 

 behig able to preserve it either in the language of philosophy or in 

 common use. Logicians cannot ma1<c the meaning of any but scien- 

 tific terms : that of all other words is made by the collective human 

 race. But logicians can ascertain clearly what it is which, working 

 obscurely, has guided the general mind to a particular employment of 

 a name ; and when they have found this, they can clothe it in such 

 distinct and j^ermanent terms, that mankind shall see the meaning 

 which before they only felt, and shall not suffer it to be afterwards 

 forgotten or misapprehended. And this is a power not lower in dignity, 

 and far less liable to abuse, than the chimerical one of domineering 

 over language. 



CHAPTER VI. 



THE PRINCrPLES OF A PHILOSOPHICAL LANGUAGE FURTHER CONSIDERED. 



§ 1. We have, thus far, considered only one of the requisites of a 

 language adapted for the investigation of truth ; that its terms shall 

 each of them convey a determinate and unmistakable meaning. There 

 are, however, as we have already remarked, other requisites ; some of 

 them important only in the second degree, but one which is funda- 

 mental, and barely yields in point of importance, if it yields at all, to 

 the ([uality which we have already discussed at so much length. That 

 the language may be fitted for its purposes, not only should every 

 word perfectly express its meaning, but there should be no important 

 meaning without its word. Whatever we have occasion to think of 

 often, and for scientific purposes, ought to have a name appropriated 

 to it. 



This requisite of philosophical language may be considered under 

 three different heads; that number of separate conditions being in- 

 volved in it. 



§ 2. First; there ought to be all such names, as are needful for 

 making such a record of individual observations that the words of the 



