WORDS. 
them. The same holds in common life in 
numberless instances. Such words some- 
times suggest the words of their definitions, 
sometimes the ideas of these words, some- 
times a particular species comprehended 
under the general term, &c. But whatever 
they suggest, it may be easily seen, that 
they derive the- power of doing it from assor 
elation. 
Lastly, there are words used in abstract 
sciences' which can scarcely be defined or 
described by other words, such as identity, 
existence, he. The use of these must there- 
fore be learned, as that of the particles 
is. Indeed children learn their first imper- 
fect notions of all the words considered in 
this and the last three paragraphs, chiefly 
in this way ; and come to more precise and 
explicit ones only by means of books, as 
they advance to adult age, or by endeavour- 
ing to use them properly in their own deli- 
berate compositions. 
From the foregoing train of reasoning the 
following inferences may be drawn. 
I . Including under the head of definition, 
description, or any way of explaining a 
VPord by other words, excepting that by a 
piere synonymous term ; and excluding from 
the head of ideas the visible idea of the cha- 
racter pf a word, and the audible pne of its 
sound, and also all ideas which are either 
extremely faint or extremely variable ; 
words may be distinguished into the four 
following classes : 1. Such as have ideas 
pnly; 2. Such as have both ideas and defi- 
nitions; 3. Such as have definitions only; 
4. Such as have neither ideas nor defini- 
tions. 
It is difficult to fix precise limits to these 
four classes, so as to determine accurately 
where each ends and the next begins ; and 
if we consider these things in the most 
general way, there is perhaps no word which 
has not both an idea and a definition ; that 
is, which is not occasionally attended with 
some one or more internal feelings, and 
which may not be explained, in some im- 
perfect manner at least, by other words. 
However the following are some instances 
pf words which have the fairest right to 
each class. Tlie names of simple sensible 
objects are of the first class. Thus white, 
sweet, &c. excite ideas, but cannot be der 
fined. Words of this class stand only for 
the stable parts of the respective ideas, not 
for the several variable particularities, cir- 
cumstances, and adjuncts, which here interr 
piix themselves. 
The names of natural bodies, animal, ve- 
getable, or mineral, are of the second class ; 
for they excite agpegates of sensible ideas, 
and at the same time may be defined by an 
enumeration of their properties and charac- 
teristics. Thus likewise geometrical figures 
have both ideas and definitions. The defi- 
nitions, in both cases, are so contrived as to 
leave out all the variable particularities of 
the ideas, and also to be more full and pre- 
cise than the ideas generally are in the parts 
which are of a permanent nature. 
Algebraic quantities, such as roots, 
powers, surds, &c. belong to the third class ; 
and have definitions only. The same may 
be said, of scientifical terms of art, and of 
most abstract general terms, moral, meta- 
physical, and vulgar. However, mental 
emotions are apt to attend some of these 
even in passing slightly over the ear, and 
these emotions may be considered as ideas 
belonging to the respective terms. Thus 
the very words, gratitude, mercy, cruelty, 
treachery, &c. separately taken, affect the 
mind; and yet, since all reasoning upon 
them is to be founded on their definitions, 
it seems best to refer them tp this third 
class. 
Lastly, the particles, the, of, to, for, but, 
&c. have neither definition nor ideas, as we 
have limited those terms, 
2. It will easily appear from the obser, 
vations here made upon words, and the as- 
sociations which adhere to them, that the 
languages of different ages and nations 
must bear a great general resemblance to 
each other, and yet have considerable par- 
ticular differences ; whence any one may be 
translated into any other, so as to convey 
the same ideas in general, and yet not with 
perfect precision and exactness. Tliey 
must resemble one another, because the 
phenomena of nature which they are all in- 
tended to express, and the uses and exi- 
gences of human life to which they minis- 
ter, have a general resemblance. But 
then, as the bodily make and genius of each 
people, the air, soil, and climate, commerce, 
arts, sciences, religion, &c. make consider- 
able differences in different ages and na- 
tions, it is natural to expect that the lan- 
guages should have proportionable diffe- 
rences in respect of each other. 
In learning a new language the words of 
it are at first substitutes for those of our 
native language ; that is, they are associat- 
ed, by means of these, with the proper ob- 
jects and ideas. AFhen this association is 
sufficiently strong, the middle bond is drop- 
