Ninthly, learning to read helps children much in the same respects ; especially as it teaches then; to separate sentences in to the several words . which compose them ; which those who cannot read are scarcely able to do, even when they arrive at adult age.
Thus we may see how children and others are enabled to understand a conti nued discourse, relating to sensible im pressions only ; and how the words, in passing over the ear, must raise up trains of visible and other ideas, by the power of association. Our next inquiry must be co»cerningthe words which denote either intellectual things, or collections of other words.
Tenthly, the words which relate to the several passions of love, hatred, hope, fear, anger, &c. being applied to the child when he is under the influence of these passions, get the power of raising up the ideas of those passions, and also the usual associated circumstances. The application of the same words to others helps also to annex the ideas of the asso ciated circumstances to them, and even of the passions themselves, both from the infectiousness of our natures, and from the power of associated circumstances to raise the passions. The words, however, denoting the passions, do not, for the most part, raise up in us any degree of the passions themselves, but only the ideas of the associated circumstances. We are supposed sufficiently to under stand the continued discourses into which these words enter, when we form true notions of the actions, particularly the visible ones, attending the feelings de noted.
Elcventhly, the names of intellectual and moral qualities and operations, stand for a description of these qualities and operations ; and therefore, if dwelt upon, excite such ideas as these descriptions in all their particular circumstances do. But the common sentences into which these words enter, pass over the mind too quick, for the most part, to allow of such delay. They are acknowledged as fami liar and correct ; and suggest certain as sociated visible ideas, and nascent inter nal feelings, taken from the description of these names, or from the words which are usually joined with them in discourses and writings.
Twelftlily, there are many terms of art in all the branches of learning, which are defined by other words, and which, therefore, are only compendious substi tutes for ;hem. The same holds in com
mon life in numberless instances. Such words sometimes suggest the words of their definitions, sometimes the ideas of these words, sometimes a particular spe cies comprehended under the general term, &c. But whatever they suggest, it may be easily seen, that they derive the power of doing it from association.
Lastly, there are words used in abstract sciences which can scarcely be defined or described by other words, such as identity, existence, &c. The use of these must therefore be learned, as that of the particles is. Indeed children learn their first imperfect notions of all the words considered in this and the last three pa ragraphs, 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 endeavouring to use them properly in their own deliberate compositions.
From the foregoing train of reasoning, the following inferences may be drawn.
1. Including tinder die head of chsfini tion, description, or any way of explain ing a word by other words, excepting. that by a mere synonymous term; and excluding from the head of ideas the vi sible idea of the character of a word, and the audible one of its sound, and also all ideas which are either extremely faint or extremely variable ; words may be dis kinguished into the four following 1. Such as have ideas only ; 2. Such as ,have both ideas and definitions ; 3. Such as have definitions only ; 4. Such as have neither ideas nor definitions.
It is difficult to fix precise limits to these four classes, so as to determine ac curately where each ends and the next begins ; and if we consider these things in the most general way, there is per haps no word which has not both an idea and a definition ; that is, which is not oc casionally attended with some one or more internal feelings, and which may not be explained, in some imperfect manner at least, by other words. How ever, the following are some instances of words which have the fairest right to each class. The names of simple sensi ble objects are of the first class. Thus white, sweet, &c. excite ideas, but cannot be, defined. Words of this class stand only for the stable parts of the respective ideas, not for the several variable parti cularities, circumstances, and adjuncts, which here intermix themselves.