2910. Seeing and hearing are opposite functions; the first indicates the creation, the latter the return of the creation into chaos.
2911. Through sight we become acquainted with the universe, through hearing with the miniature universe, or man. Sight passes out of us, hearing into us; or through sight Man is posited in the world, through hearing among his fellow-men. Sight is the speech of the world, hearing that of the planet.
2912. Sight is the speech or language of the universe, hearing the language of Man. Through sight the world reveals unto us its spirit or its thoughts; but through hearing man only discloses what are his own. As words are but the representations of the disintegrated body of Man, so are the world-forms the representatives of the disintegrated body of the primary spirit. The word is a rigidified, crystallized thought of Man; a natural body is a rigidified, crystalline thought of the primary act—a word of God.
2913. Through hearing self-consciousness originates; through sight consciousness of the world, universal consciousness. By means of the former we only become acquainted with human relations—which is understanding; by the latter with those that are universal—this being reason.
2914. Without the ear there would be no understanding, without the eye no reason.
2915. Understanding is microcosm, reason macrocosm. From what is intelligent we expect human wisdom, from what is rational world-wisdom.
2916. That the light also has a medium, whereby it acts upon us, is at once evident from our existing in such a medium; but it could also act directly upon us, were it not inevitably broken up beforehand into colours in traversing the media. All terrestrial elements may be a medium for the transmission of light, such as the gaseous, fluid, and solid, i. e. if they are transparent.
2917. We perceive only coloured light, because our organ of light is only a rigidified colour, a material light. There is no pure light for us; there is none also in general.
2918. Sight is thus a terrestrial light-tension, a colour-becoming.
2919. This happens only through refraction. The eye is a refracting medium. It is distinguished from the brain by being a translucent, refractive, encephalic substance.