The idea of a separable conscious personal force, or spirit, that leaves the body at death, serves also, as it gathers strength, to explain sleep, fainting, epilepsy; and sometimes every sickness is attributed to the partial detachment or desertion of the spirit; which, therefore, it is the doctor’s business to plug in, or to catch and restore; or (if I rightly remember a report of Miss Kingsley’s) he may even supply another one from a basketful of souls kept at hand for such exigencies. That the ghost theory arises not only from dreams, but is also suggested by hallucinations and hypnagogic visions is very probable. In various parts of the world savages have been described as having visions of remarkably coherent and convincing vividness that seem not to have been dreams.[180] But such experiences, even when artificially induced by fasting or drugs (as happens among many tribes), are rare in comparison with dreams; and to the influence of dreams upon these savage beliefs there is abundant testimony. With some tribes dreams are treated as part of their objective experience; so that to be injured by your neighbour in a dream is just ground for avenging yourself as soon as you wake; and to see a dead man in a dream is, therefore, clear proof of his continued existence, and that either he has come to the dreamer or the dreamer has gone to visit him. Thus Sir Everard im Thurn says of the native of Guiana, his dreams are as real as any events of his waking life; his dream-actions are done by his spirit: in dreams he continues to see the dead—that is, their spirits.[181] Similarly, the Lengua Indians (W. of R. Paragua) have great faith in dreams; wherein the spirit is believed to leave the body and to do in fact what is dreamed.[182] According to the Cherokees, to dream of being bitten by a snake requires the same treatment as actual snake-bite; else (perhaps years later) the same inflammation will appear in the wounded spot, with the same consequences.[183] The Motu hold that _sua_ (ghosts or spirits) are seen in dreams, and that when a man sleeps his own _sua_ leaves his body.[184] “The Lifuans believe in the reality of what is seen in a dream, and are influenced by it. Their dead ancestors appeared in dreams.”[185] And the Polynesians of Manatuki thought that “dreams were occasioned by the spirit going to the places seen in them.”[186] Many more of such witnesses might be cited.