Greek Texts & Translations

The third organ of perception within us which we have to describe in our survey is that of hearing, 67band the causes whereby its affections are produced. In general, then, let us lay it down that sound is a stroke transmitted through the ears, by the action of the air upon the brain and the blood, and reaching to the soul; and that the motion caused thereby, which begins in the head and ends about the seat of the liver, is “hearing”; and that every rapid motion produces a “shrill” sound, and every slower motion a more “deep” sound; and that uniform motion produces an “even” and smooth sound and the opposite kind of motion a “harsh” sound; 67cand that large motion produces “loud” sound, and motion of the opposite kind “soft” sound. The subject of concords of sounds must necessarily be treated in a later part of our exposition. ^note

We have still remaining a fourth kind of sensation, which we must divide up seeing that it embraces numerous varieties, which, as a whole, we call “colors.” This consists of a flame which issues from the several bodies, and possesses particles so proportioned to the visual stream as to produce sensation; and as regards the visual stream, we have already stated ^note merely the causes which produced it. 67dConcerning colors, then, the following explanation will be the most probable and worthy af a judicious account. Of the particles which fly off from the rest and strike into the visual stream some are smaller, some larger, and some equal to the particles of the stream itself; those, then, that are equal are imperceptible, and we term them “transparent”; while the larger and smaller particles—of which the one kind contracts, the other dilates the visual stream—are akin to the particles of heat and cold which affect the flesh, 67eand to the astringent particles which affect the tongue, and to all the heating particles which we call “bitter“ ^note with these “white” and “black” are really identical affections, occurring in a separate class of sensation, although they appear different for the causes stated. These, therefore, are the names we must assign to them: that which dilates the visual stream is “white” and the opposite thereof “black“ ^note; and the more rapid motion, being that of a different species of fire, which strikes upon the visual stream and dilates it as far as to the eyes, and penetrating 68aand dissolving the very passages of the eyes causes a volume of fire and water to pour from them, which we call “tears.” And this moving body, being itself fire, meets fire from the opposite direction; and as the one firestream is leaping out like a flash, and the other passing in and being quenched in the moisture, in the resultant mixture colors of all kinds are produced. This sensation we term “dazzling” and the object which causes it “bright” or “brilliant.” Again, when the kind of fire 68bwhich is midway between these ^note reaches to the liquid of the eyes and is mingled therewith, it is not brilliant but, owing to the blending of the fire's ray through the moisture, it gives off a sanguine color, and we give it the name of “red.” And “bright” color when blended with red and white becomes “yellow.” But in what proportions the colors are blended it were foolish to declare, even if one knew, seeing that in such matters one could not properly adduce any necessary ground or probable reason. Red blended with black and white makes “purple”; 68cbut when these colors are mixed and more completely burned, and black is blended therewith, the result is “violet.” “Chestnut” comes from the blending of yellow and grey; and “grey” from white and black; and “ochre” from white mixed with yellow. And when white is combined with “bright” and is steeped in deep black it turns into a “dark blue” color; and dark blue mixed with white becomes “light blue”; and chestnut with black becomes “green.” As to the rest, it is fairly clear from these examples