all empiricists are guilty of. The Stoics take the opposite course of finding essential Being in the object of thought or the universal; and they fail equally in reaching the content, temporal existence, which, however, they most inconsistently assume. We have here the metaphysics of Epicurus; nothing that he says farther on this head is of interest. 3. PHYSICS. The natural philosophy of Epicurus is based on the above foundation; but an aspect of interest is given it by the fact that it is still peculiarly the method of our times; his thoughts on particular aspects of Nature are, however, in themselves feeble and of little weight, containing nothing but an ill-considered medley of all manner of loose conceptions. Going further, the principle of the manner in which Epicurus looks on nature, lies in the conceptions he forms, which we have already had before us (pp. 282, 285). That is to say, the general representations which we receive through the repetition of several perceptions, and to which we relate such perceptions in forming an opinion, must be then applied to that which is not exactly matter of perception, but yet has something in common with what we can perceive. In this way it comes about that by such images we can apprehend the unknown which does not lend itself immediately to perception; for from what is known we must argue to what is unknown. This is nothing else but saying that Epicurus judged by analogy, or that he makes so-called evidence the principle of his view of Nature; and this is the principle which to this day has authority in ordinary physical science. We go through experiences and make observations, these arising from the sensuous perceptions which are apt to be overlooked. Thus we reach general concepts, laws, forces, and so on, electricity and magnetism, for instance, and these are then applied by us to such objects and activities as we cannot ourselves directly perceive. As an example, we know about the nerves and their connection with the brain; in order that there may be feeling and so on, it is said that a transmission from the finger-tips to the brain takes place. But how can we represent this to ourselves? We cannot make it a matter of observation. By anatomy we can lay bare the nerves, it is true, but not the manner of their working. We represent these to ourselves on the analogy of other phenomena of transmission, for instance as the vibration of a tense string that passes through the nerves to the brain. As in the well-known phenomenon of a number of billiard balls set close together in a row, the last of which rolls away when the first is struck, while those in the middle, through each of which the effect of the stroke has been communicated to the next, scarcely seem to move, so we represent to ourselves the nerves as consisting of tiny balls which are invisible even through the strongest magnifying glass, and fancy that at every touch, &c., the last springs off and strikes the soul. In the same way