Since the spirit is only occasionally visible and still more rarely tangible, and since in general the relations of the living to it are somewhat vague and dim, there is a tendency to regard it as being itself shadowy and unsubstantial. But on this point primitive thought vacillates a great deal. We often find the spiritual body represented as existing and behaving in much the same manner as an ordinary body. It is sometimes represented as eating and drinking, wrestling and fighting, and sometimes intermarrying with the living. Marriage between a living person and a disembodied spirit is not uncommon in Chinese folklore. But these are exceptional cases. Familiar dealings with spirits are most often supposed to be the privilege of magicians and medicinemen, who often make it a regular part of their profession to catch departed souls in snares, and either detain them in custody, or bring them back to the body to which they belong.

If there are two material impersonations of one individual, there is no reason in the nature of the case why there should not be more. As a matter of fact we find that primitive thought often recognises the existence of several. The explanation of shadows and reflexions by optical laws is beyond the range of the savage mind; they are accordingly interpreted in accordance with the system of ideas familiar to primitive thought. They are impersonations of the whole individual, much as the soul is; sometimes they seem to be identified with the soul, but they are often regarded as distinct. There is a Polynesian story of a girl who stole a young man's shadow and imprisoned it in a bottle; she then set it free and projected it upon a pool of water. "As the man moved about in his own land, so the shadow moved on the water."

Sometimes different impersonations are supposed to have different functions. Thus the Tshispeaking people of the Gold Coast ascribe to each individual two impersonations besides his body, — the srahman, or soul, and the kra. The kra is especially connected with the phenomena of dreaming, and of birth and heredity. In dreams and visions it passes out of the body; after death it acquires connexion with some other body, so that each man's kra has passed through a long series of distinct embodiments. The srahman, or soul, cannot leave the body without suspension of obvious vital functions. After death, it passes to deadland, which in its social and other arrangements is a counterpart of the world in which it has previously lived. If the man has died before completing the proper term of life, the srahman lingers about its former habitation. During life, body, srahman, and kra are regarded as different impersonations of the same individual, so that what happens to any of them may affect the whole. The incidents in a dream are believed to be adventures of the kra. "If a native, having taken a chill overnight, awakes in the morning with stiff and aching muscles, and the usual symptoms of muscular rheumatism, he at once concludes that during the night his kra has been engaged in some toilsome pursuit, or in a conflict with another kra, and he attributes the pain he feels to the exertions made or the blows inflicted."* Here the locally separate experience of the kra is the experience of the whole man, including the soul and body.

* Ellis, The Tshispeaking Peoples of the Gold Coast of Africa, p. 151. Pearson's Magazine, March, 1898, p. 255.

The primitive view of the internal Self as a counterpart of the external body has only been very gradually displaced by the growth of civilisation. Even among ourselves at the present day it is very far from being extinct. People still believe in ghosts which appear under the form and even in the clothes of the living person. It is true that these ghosts are for the most part regarded as very attenuated forms of matter, and there is a popular impression that they are impalpable, although visible. But they are sometimes represented as being very palpable indeed. There is one described in a popular monthly magazine which "twisted up gunbarrels like so much soft paper."

The first clear conception of a purely immaterial principle is probably to be ascribed to Plato. But long after Plato the old notion of spirit as an attenuated form of matter survived even in scientific thinking. As the progress of thought and knowledge brought into clearer light the unity and continuity of nature, the conception of the material soul became modified. There was a tendency to explain its origin as part of the general course of physical nature, and its resemblance to the external body was no longer insisted on. The view taken was that life and thought were properties of a certain form of matter diffused throughout the physical universe. The cue to this theory was given by the phenomena of breathing and of vital heat. The general soulsubstance from which individual souls were supposed to be derived was air rarefied by heat. The best examples of doctrines of this kind are to be found among the preSocratic philosophers. Anaximenes regards the soul as being essentially air, and air as being essentially of the nature of soul. Air in general is to the universe what our own soul is to us. Heracleitus regards breathing as a connexion between the internal soul and the surrounding air from which it is originally derived. In later times, when the doctrine of an immaterial soul became generally accepted, the old material soul was still very commonly assumed to exist together with it, and to constitute a link between it and the body. We often find a division of psychical functions between the material, and immaterial souls. Ethical and religious functions were often ascribed to the immaterial principle, while all lower functions, such as sensation, perception, appetite, and the like, were ascribed to the material principle. Even in comparatively recent times, we sometimes find the immaterial soul recognised only by way of submission to theological dogma, all ordinary conscious functions being ascribed to material soul. Thus Bacon says: "The sensible soul — the soul of brutes — must clearly be regarded as a corporeal substance, attenuated and made invisible by heat; a breath (I say) compounded of the natures of flame and air, having the softness of air to receive impressions, and the vigour of fire to propagate its action."* To this sensible soul he appears to ascribe such faculties as "understanding, reason, imagination, memory, appetite, will." He demands that "the origin of these faculties" should be "handled physically as they are innate and inherent in the [sensible] soul."* The uncreated and immortal immaterial principle cannot be investigated in this way; it is a topic for theologians, and it is very difficult to see what Bacon has left for it to do.

* Works (spedding and Ellis), vol. iv., p. 398.

The last important survival of the doctrine of the material soul in scientific thought is contained in the doctrine of "animal spirits," as held, for example, by Descartes. The animal spirits consist of a fine form of matter constituting a connecting link between the body and the soul, but they are no longer regarded as themselves capable of any kind of conscious experience. They are merely part of the mechanism by which the immaterial principle acts on the body and is acted on by it. Thus the material soul for Descartes is a soul no longer; it is merely a mode of matter, and like all other matter sharply and rigidly distinguished from all conscious existence. With the advance of modern physiology, it became displaced even from this position, and was recognised as a figment.