The beginnings of morality can no more be discovered historically than the beginnings of religion. Language, in various nations, implies that it springs out of custom. The foundation of practical ethics, whatever may be the ultimate interpretation of such terms as duty and conscience in more advanced cultures, lies in social usage. When any custom is established with sufficient strength to serve as a rule demanding observance, so that its breach evokes some feeling, the seed of morals is already germinating. No group however small, no society however crude, can cohere { 199} without some such customs. They may be formed in various ways; they are strengthened by habitual repetition; they acquire the sanction of the past, they are usually referred, when men have begun to ask how they came into being--just as they ask about their own origin--to some great First Man, or some superhuman personality in the realm above (p. 171). But always there are some things allowable, and others forbidden: some things may (or even must) be done, others may not.
When custom has gained this power, it carries with it an element of control. Impulse must not be inconsiderately indulged, it must be governed. Private interests must be subordinated to a rule, and conduct conformed to a standard of behaviour. In the ruder culture, where the supply of food is of urgent importance, such rules gather around the produce of the chase or of the ground. Among the Australian Kurnai, for example, all game caught by the men, all roots or fruits collected by the women, must be shared with others according to definite arrangements. Methodic distribution is obligatory, and self-denial in sharing and eating is thus impressed upon the young. Moreover certain varieties of food are strictly forbidden to women, children, and boys before initiation.
Prohibitions of this kind, extending over many branches of conduct, are found all over the world. They are often designated by a { 200} term in use in Polynesia, taboo (_tabu_ or _tapu_). Their origin has been much disputed, owing to the extraordinary complexity of the circumstances with which they are concerned. Taboo contains emphatically an element of mystery. It comes out of a vague dim background, and implies that some strange power will be set in perilous operation if a certain thing is done. Such a power, obscure, indefinite, not personalised, but mightier than men, has been recognised at the base of religion under another term, the Melanesian _mana_ (p. 80). Taboo has been accordingly described as a negative _mana_. It is a prohibition against calling the weird uncanny force into the open, where it may do unexpected hurt.