If, then, as I cannot but think, the arrangement of the mental phenomena, as belonging to two classes of powers, the intellectual and the active, be at once incomplete, and not accurate, even to the extent to which it reaches, it may be worth while to try at least some other division, even though there should not be any very great hope of success. Though we should fail in our endeavour to obtain some more precise and comprehensive principle of arrangement, there is also some advantage gained, by viewing objects, according to new circumstances of agreement or analogy. We see, in this case, what had long-passed before us unobserved, while we were accustomed only to the order and nomenclature of a former method; for, when the mind has been habituated to certain classifications, it is apt, in considering objects, to give its attention only to those properties which are essential to the classification, and to overlook, or at least comparatively to neglect, other properties equally important and essential to the very nature of the separate substances that are classed, but not included in the system as characters of generic resemblance. The individual object, indeed, when its place in any system has been long fixed and familiar to us, is probably conceived by us less, as an _individual_, than as one of a class of individuals, that agree in certain respects, and the frequent consideration of it, as one of a class, must fix the peculiar relations of the class, more strongly in the mind, and weaken proportionally the impression of every other quality that is not so included. A _new_ classification, therefore, which includes, in its generic character, those neglected qualities, will of course draw to them attention, which they could not otherwise have obtained; and, the more various the views are, which we take of the objects of any science, the juster consequently, because the more equal, will be the estimate which we form of them. So truly is this the case, that I am convinced, that no one has ever read over the mere terms of a new division, in a science, however familiar the science may have been to him, without learning more than this new division itself, without being struck with some property or relation, the importance of which he _now_ perceives most clearly, and which he is quite astonished that he should have overlooked so long before.