Things that harm vision include activities and movements, as well as food and the degree to which it is absorbed. Activities and movement include everything that is drying, for example, frequent copulation, prolonged looking at shiny objects, excessively long reading of finely written letters, while in these matters it is useful to stick to the middle. Delicate work and sleeping on a full stomach immediately after dinner are also harmful. On the contrary, one who suffers from weak vision must wait until the food is digested. Any overflow is harmful to vision, as well as everything that dries out the nature, and all salty, spicy and other substances that form a sediment in the blood. Intoxication is also harmful to vision. But vomiting is useful because it cleanses the stomach, but it is also harmful to vision because it moves matter in the brain and drives ic to the eye. If vomiting cannot be avoided, then it should be induced after eating and without straining. Frequent bathing in a bathhouse is harmful to vision, as is excessive sleep, excessive crying and excessive bleeding, especially the continuous application of blood-sucking cups. Among the foods that are harmful are those that are salty, spicy, steamy, and those that cause suffering in the mouth of the stomach: thick cloudy wine, leeks, onions, mountain basil, ripe olives, dill, cabbage and lentils.