In the stage of our conscious life which we may call, relatively to man’s growth, primeval, certain bodily acts and states and certain material substances are regarded as unclean and impure, likely to imprint a stain upon the person. It is impossible here to attempt to enumerate all the examples, and it is enough to mention a few that are salient and typical. The generative processes of life, the states and activities of the male and especially the female organism connected with them, the bodily changes incident on puberty, are among the most familiar phenomena with which the idea of impurity in some peculiar sense has been universally associated. A chief centre or {90} “nidus” of impurity is child-birth; but still more dangerously impure is its counterpart, death and all the phenomena of death. In respect of child-birth the idea is fading away from our civilised consciousness; but it has left a deep deposit in our conscious or subconscious self in regard to death. The material substance that has been most generally felt to be impure is blood; the curious feeling that the mere mention of the word often excites in certain modern people is a faint reflex of the savage mental state in respect to the thing; and the influence of this disposition upon advanced society raises the most interesting question in which comparative law, ethics, and religion are jointly concerned, and which will be considered later. To continue our enumeration we may not find that the objects of the inanimate world outside ourselves are usually regarded by primitive thought as in themselves impure, but all or most of them are capable of catching the infection from ourselves, from death or child-birth {91} for instance: hence it may be necessary to break or destroy or purify the utensils and furniture of the house where a death or a birth has occurred. At a somewhat more advanced stage, certain food-stuffs come to rank as impure, and a complicated code of “tapu” is established for specially sanctified persons. Then we are confronted, but not apparently in the most primitive period, with the distinction between pure and impure animals, which also dictates certain rules and practices of diet.