+24+. As the soul was conceived of as an independent being, it was natural that it should be held to have a form like that of the external body--it could not be thought of otherwise.[31] This opinion was doubtless confirmed in the savage mind by such experiences as dreams, visions, hallucinations, and illusions, and by such phenomena as shadows and reflections. The dreamer believed that he had been far away during the night, hunting or fighting, and yet the testimony of his comrades convinced him that his body had not left its place; the logical conclusion was that his inner self had been wandering, and this self, as it seemed to him, had walked, eaten, hurled the spear, done all that the ordinary corporeal man would do. In dreams he saw and conversed with his friends or his enemies, all in corporeal form, yet all of them asleep in their several places; their souls also, he concluded, were wandering. Even in his waking hours, in the gloom of evening or on some wide gleaming plain, he saw, as he thought, shadowy shapes of persons who were dead or far away, and heard mysterious voices and other sounds, which he would naturally refer to the inner self of the absent living or the dead. Reproductions of himself and others appeared on land and in water. All such experiences would go to convince him that there were doubles of himself and of others, and that these were corporeal--only dim, ethereal, with powers greater than those of the ordinary external body. +25+. While the soul of the living man was most commonly conceived of as a sublimated replica of the ordinary body, it was also supposed in some cases to take the form of some animal--an opinion that may have arisen as regards any particular animal from its appearance at a time when the soul was supposed to be absent from the body,[32] and is to be referred ultimately to the belief in the identity of nature of animals and man. The souls of the dead also were sometimes supposed to take the shape of animals, or to take up their abode in animals[33] or in trees (as in Egypt): such animals (tigers, for example) were commonly dangerous, and this theory of incarnation is an expression of the widely diffused belief in the dangerous character of the souls of the dead. In later, cultivated times the bird became a favorite symbol of the soul--perhaps from its swift and easy flight through the air.[34]