 We perceive a distant body because light travels from that body to our sense organ and does something to the sense organ. The light does not add new motion to the sense organ; that is absurd. Instead, the light re-directs the bodies of the sense organ to form a pattern of the distant body. In the very next sentence Cavendish offers the same account of the causal process by which a creature acquires a disease: she says that “as for infectious Diseases, they come by corporeal imitation, as by touch, either of the infected air, drawn in by breath, or entring through the Pores of the Body, or of some things brought from infected places…” (ibid.). For Cavendish, occasional causation occurs by contact when a body re-directs the self-motion of a second body. Bodies interact with other bodies by contact, when they hinder each other and they re-direct (but never transfer) motion. In the case of perception, the self-motions of the sense organ pattern an image of the distant body upon the arrival of light (or some other medium). As we would expect, Cavendish does not hold that light travels all the way from the distant body; instead, that light is patterned by air or light that is in the plenum of matter that lies in-between object and perceiver, and in the end the sense organ patterns that air or light. She says that “as for air, it patterns out the light of the Sun, and the sensitive motions in the eyes of animals pattern out the light in the air” (Cavendish 1664, 83). She owns as a consequence that in the plenum that is the material universe there is a lot of patterning that takes place that we do not notice; there are objects that we and other creatures pattern but that are below the threshold of awareness (Cavendish 1668a, 211). The same bit of light does not travel all the way from object to perceiver; nor does light pass through walls. Instead, patterning abounds, along the lines of Newton’s Cradle.