Passing from life to mind, we find Empedocles teaching an even more pronounced materialism than Parmenides, inasmuch as it is stated in language of superior precision. Our souls are, according to him, made up of elements like those which constitute the external world, each of these being perceived by a corresponding portion of the same substances within ourselves—fire by fire, water by water, and so on with the rest. It is a mistake to suppose that speculation begins from a subjective standpoint, that men start with a clear consciousness of their own personality, and proceed to construct an objective universe after the same pattern. Doubtless they are too prone to personify the blind forces of Nature, and Empedocles himself has just supplied us with an example of this tendency, but they err still more by reading outward experience into their own souls, by materialising the processes of consciousness, and resolving human personality into a loose confederacy of inorganic units. Even Plato, who did more than anyone else towards distinguishing between mind and body, ended by laying down his psychology on the lines of an astronomical system. Meanwhile, to have separated the perception of an object from the object itself, in ever so slight a degree, was an important gain to thought. We must not omit to notice a hypothesis by which Empedocles sought to elucidate the mechanism of sensation, and which was subsequently adopted by the atomic school; indeed, as will presently be shown, we have reason to believe that the whole atomic theory was developed out of it. He held that emanations were being continually thrown off from the surfaces of bodies, and that they penetrated into the organs of sense through fine passages or pores. This may seem a crude guess, but it is at any rate much more scientific than Aristotle’s explanation. According to the latter, possibilities of feeling are converted into actualities by the presence of an object. In other words, we feel when and because we do; a safe assertion, but hardly an addition to our positive knowledge of the subject.