Vitae philosophorum

We must also consider that it is by the entrance of something coming from external objects that we see their shapes and think of them.[*](Thought, as well as vision, is explained by images, but images of a much finer texture, which fail to affect the eyes but do affect the mind: cf. Fr. 317 (Us.); Lucr. iv. 777 f.) For external things would not stamp on us their own nature of colour and form through the medium of the air which is between them and us,[*](This was the view of Democritus; cf. Beare, Greek Theories of Elementary Cognition, p. 26.) or by means of rays of light or currents of any sort going from us to them, so well as by the entrance into our eyes or minds, to whichever their size is suitable, of certain films coming from the things themselves, these films or outlines being of the same colour and shape as the external things themselves.

They move with rapid motion;[*](The reader is left to infer that, the more rapid the motion, the more continuous is the succession of fresh images. It is this uninterrupted train of images which guarantees the continued existence of the external object, just as their similarity or identity guarantees its oneness: cf. Lucr. iv. 87, 104 f., 189, 256 f., 714 f.; Cic. N.D. i. 105.) and this again explains why they present the appearance of the single continuous object, and retain the mutual interconnexion which they had in the object, when they impinge upon the sense, such impact being due to the oscillation of the atoms in the interior of the solid object from which they come. And whatever presentation we derive by direct contact, whether it be with the mind or with