.Natur e in their view is an artistically working fire, going on its way to create ; which is equivalent to a fiery, creative, or fashioning breath. And the soul is a nature capable of perception. And they regard it as the breath of life, congenital with us ; from which they infer first that it is a body and secondly that it survives death. Yet it is perishable, though the soul of the universe, of which the individual souls of animals are parts, is indestructible. Zeno of Citium and Antipater, in their treatises De anima, and Posidonius define the soul as a warm breath ; for by this we become animate and this enables us to move. Cleanthes indeed holds that all souls continue to exist until the general conflagration ; but Chrysippus says that only, the souls of the wise do so. a They count eight parts of the soul : the five senses, the generative power in us, our power of speech, and that of reasoning. They hold that we see when the light between the visual organ and the object stretches in the form of a cone : so Chrysippus in the second book of his Physics and Apollodorus. The apex of the cone in the air is at the eye, the base at the object seen. Thus the thing seen is reported to us by the medium of the air stretching out towards it, as if by a stick. We hear when the air between the sonant body and the organ of hearing suffers concussion, a vibration which spreads spherically and then forms waves and strikes upon the ears, just as the water in a reservoir forms wavy circles when a stone is thrown into it. Sleep is caused, they say, by the slackening of the tension in our senses, which affects the ruling part of