Seite - 864 - in The Complete Aristotle

Empedocles at times seems to hold that vision is to be explained as above stated by light issuing forth from the eye, e.g. in the following passage:— < div class=“quote”> As when one who purposes going abroad prepares a lantern, A gleam of fire blazing through the stormy night, Adjusting thereto, to screen it from all sorts of winds, transparent sides, Which scatter the breath of the winds as they blow, While, out through them leaping, the fire, i.e. all the more subtile part of this, Shines along his threshold old incessant beams: So [Divine love] embedded the round “lens”, [viz.] the primaeval fire fenced within the membranes, In [its own] delicate tissues; And these fended off the deep surrounding flood, While leaping forth the fire, i.e. all its more subtile part-. Sometimes he accounts for vision thus, but at other times he explains it by emanations from the visible objects. Democritus, on the other hand, is right in his opinion that the eye is of water; not, however, when he goes on to explain seeing as mere mirroring. The mirroring that takes place in an eye is due to the fact that the eye is smooth, and it really has its seat not in the eye which is seen, but in that which sees. For the case is merely one of reflexion. But it would seem that even in his time there was no scientific knowledge of the general subject of the formation of images and the phenomena of reflexion. It is strange too, that it never occurred to him to ask why, if his theory be true, the eye alone sees, while none of the other things in which images are reflected do so. True, then, the visual organ proper is composed of water, yet vision appertains to it not because it is so composed, but because it is translucent—a property common alike to water and to air. But water is more easily confined and more easily condensed than air; wherefore it is that the pupil, i.e. the eye proper, consists of water. That it does so is proved by facts of actual experience. The substance which flows from eyes when decomposing is seen to be water, and this in undeveloped embryos is remarkably cold and glistening. In sanguineous animals the white of the eye is fat and oily, in order that the moisture of the eye may be proof against freezing. Wherefore the eye is of all parts of the body the least sensitive to cold: no one ever feels cold in 864