I have by no means given a complete category of the primitive and barbarous peoples who believe in a separate soul, and who believe in a future state much like the present and in conformity with that belief bury arms, ornaments, and utensils with the dead or place them on the grave, and who slaughter horses, camels, wives, slaves, etc., in order that the deceased may retain his possessions. How far these customs extend in case of the death of woman I do not know, but as with most of these people the women are regarded as chattels of the males, the case is doubtless very different. Now as to the origin of these beliefs and customs, their causes naturally fall into two categories, the physical and the metaphysical. Modern biological science regards the whole question from the physical side almost exclusively, and facts and experiences that belong largely or exclusively to the metaphysical realm are warped out of their natural order to fit the theory of interpretation. Every savage observes not only that he casts a shadow, but that shadows attend all inanimate objects that stand so as to intercept the light, and as shadows move as do objects that gives rise to the idea of animation. Hence we have genii, dryads, naiads, ghosts, angels, demons, etc. To fortify this belief we have echoes, which give voice to animate and inanimate objects. Movement and voice are the universal accompaniment of animation. The part played by the breath, and its sudden cessation at death, are believed to contribute to the belief in invisible existences. The beating of the heart, and its cessation at death, adds another link to the chain of phenomena, going to show that _something_ leaves the body at death. This may be the origin of the sacrifice of the hearts of captives to the gods, or to a deceased warrior or chief as with the ancient Mexicans, with the belief that the heart is the seat of the soul, and the soul of the captive or victim shall attend the departed chief in the other world. But the most important place should doubtless be assigned to dreams as giving rise to belief in the world of spirits. Dreams are universal amongst men, and animals like the dog also dream. Most if not all primitive people are also aware that fasting promotes dreaming, and while many of them practice long fasting, partly, no doubt, to increase fortitude and bodily endurance, in very many cases it is known to be practiced for the purpose of promoting dreams. Beyond this voluntary fasting there is the enforced fast due to famine or the scarcity of food. It will be noticed in many of the cases cited how much stress is laid on the phenomena of dreams and how literally they are interpreted.