 Habits are socially shaped dispositions to particular forms of activity or modes of response to the environment. They channel impulses in specified directions, toward certain outcomes, by entrenching particular uses of means, prescribing certain conduct in particular circumstances. While individuals may have idiosyncratic habits, the most important habits are customs, shared habits of a group that are passed on to children through socialization. Customs originate in purposive activity. Every society must devise means for the satisfaction of basic human needs for food, shelter, clothing, and affiliation, for coping with interpersonal conflict within the group and treatment of outsiders, for dealing with critical events such as birth, coming of age, and death.  Customary ways of satisfying needs shape the direction of impulse in the socialized individual. A young child just starting on solid food may be open to eating nearly anything. But every society limits what it counts as edible. Certain foods become freighted with social meaning —as suitable for celebrating birthdays, good for serving to guests, reserved for sacrifice to the gods, or fit only for animals. The child’s hunger becomes refined into a taste for certain foods on particular occasions. She may recoil in disgust or horror from certain edibles deemed taboo or unclean. There may have been a rationale for the original selection of foods. Perhaps some food was deemed taboo when its consumption was followed by a natural disaster, and people concluded that the gods were angry at them for consuming it. But the habit of avoiding it may persist long after its original rationale is forgotten (E 39–48, HNC 15–21, 43–7).