1. Above[161] we suggested the question whether it be possible to see without some medium such as the air or a diaphanous body[162]; we shall now try to consider it. It has already been asserted that in general the soul cannot see or feel without the intermediation of some body; for, when completely separated from the body (the soul dwells in the intelligible world). But, as touch consists of perception, not indeed of intelligible entities, but only of sense-objects, the soul cannot see or feel without the intermediation of some body; for when completely separated from some body, the soul dwells in the intelligible world. But, as touch consists of perception, not indeed of intelligible entities, but only of sense-object, the soul in order to come in contact with these sense-objects, must enter into cognitive or affective relation with them by the means of intermediaries which must possess an analogous nature; and that is why the knowledge of bodies must be acquired by the means of corporeal organs. Through these organs which are so interrelated as to form a sort of unity, the soul approaches sense-objects in a manner such as to establish effective communion. That contact between the organ and the cognized object must be established is evident enough for tangible objects, but is doubtful for visible objects. Whether contact be necessary for hearing is a question we shall have to discuss later.[163] Here we shall first discuss whether sight demand a medium between the eye and color. REFUTATION OF ARISTOTLE'S INSISTENCE ON A MEDIUM OF SIGHT. If a medium of sight exist, it exists only by accident, and in no way contributes to sight.[164] Since opaque and earthy bodies hinder sight, and as we see so much the better as the medium is more subtle, it may be said, indeed, that mediums contribute to sight, or at least, if they do not contribute such thereto, they may be hindrances as slight (as possible); but evidently a medium, however refined, is some sort of an obstacle, however slight. THOUGH THE MEDIUM EXPERIENCE AFFECTION, THE ORGANS FEEL IT BETTER WITHOUT THE MEDIUM.