position, and looks very paradoxical; but it is nevertheless the fact, and we must accept it as we find it. It utterly overthrows the Lockian school of philosophy, for it proves that there is something in the mind which neither entered by the way of outward experience, nor was generated by internal experience, or by what Locke calls reflection on our own mental operations. That on the presentation of one object I should be able, indeed, that I should be necessitated, to think of another object as well, this is a fact which discredits altogether the philosophy of sensational experience. If this philosophy would make good its ground, it must prove that we cannot think of more than we have actually experienced, and that it in the course of our experience, we had only seen twelve men, it would be impossible for us to think of a thirteenth; but such a proof is manifestly impossible, and such a conclusion would be absurd. My position is, that supposing we had never seen more than one man, we must, in thinking him, view him as an instance, and viewing him thus, we must virtually think an indefinite number of men. This is so far an explanation of what is meant by all thought being a passing from the singular to the universal.
23. In attempting to expound the nature of ideas, with the special view of throwing light on what Plato understood by them, I touched, in the concluding paragraphs of my last lecture, on two of their chief characteristics; these were, their necessity and
