ceived, and the other makes them a work of the mind. Let us begin with this last opinion. It consists in supposing that the relations are given to things by the mind itself. These relations have been termed categories. The question of categories plays an important part in the history of philosophy. Three great philosophers, Aristotle, Kant, and Renouvier have drawn up a list, or, as it is called, a table of them, and this table is very long. To give a slight idea of it, I will quote a few examples, such as time, space, being, resemblance, difference, causality, becoming, finality, &c.
By making the categories the peculiar possession of the mind, we attribute to these cognitions the essential characteristic of being anterior to sensation, or, as it is also termed, of existing a priori: we are taught that not only are they not derived from experience, nor taught us by observation, but further that they are presupposed by all observation, for they set up, in scholastic jargon, the conditions which make experience possible. They represent the personal contribution of the mind to the knowledge of nature, and, consequently, to admit them is to admit that the mind is not, in the presence of the world, reduced to the passive state of a tabula rasa, and that the faculties of the mind are not a transformation of sensation. Only these categories do not supplement sensation, they
