Turning now from the choice of words to their sequence, we find the same principle hold good. We have _a priori_ reasons for believing that there is some one order of words by which every proposition may be more effectively expressed than by any other; and that this order is the one which presents the elements of the proposition in the succession in which they may be most readily put together. As in a narrative, the events should be stated in such sequence that the mind may not have to go backwards and forwards in order to rightly connect them; as in a group of sentences, the arrangement should be such that each of them may be understood as it comes, without waiting for subsequent ones; so in every sentence, the sequence of words should be that which suggests the constituents of the thought in the order most convenient for building it {340} up. Duly to enforce this truth, and to prepare the way for applications of it, we must analyze the mental act by which the meaning of a series of words is apprehended. We cannot more simply do this than by considering the proper collocation of substantive and adjective. Is it better to place the adjective before the substantive, or the substantive before the adjective? Ought we to say with the French—_un cheval noir_; or to say as we do—a black horse? Probably, most persons of culture will say that one order is as good as the other. Alive to the bias produced by habit, they will ascribe to that the preference they feel for our own form of expression. They will expect those educated in the use of the opposite form to have an equal preference for that. And thus they will conclude that neither of these instinctive judgments is of any worth. There is, however, a psychological ground for deciding in favour of the English custom. If “a horse black” be the arrangement, then immediately on the utterance of the word “horse,” there arises, or tends to arise, in the mind, an idea answering to that word; and as there has been nothing to indicate what _kind_ of horse, any image of a horse suggests itself. Very likely, however, the image will be that of a brown horse: brown horses being the most familiar. The result is that when the word “black” is added, a check is given to the process of thought. Either the picture of a brown horse already present to the imagination has to be suppressed, and the picture of a black one summoned in its place; or else, if the picture of a brown horse be yet unformed, the tendency to form it has to be stopped. Whichever is the case, some hindrance results. But if, on the other hand, “a black horse” be the expression used, no mistake can be made. The word “black,” indicating an abstract quality, arouses no definite idea. It simply prepares the mind for conceiving some object of that colour; and the attention is kept suspended until that object is known. If, then, by {341} precedence of the adjective, the idea is always conveyed rightly, whereas precedence