Here, in an order of existence almost infinitely below man, we have an individual life existing in a physical form, passing from it and, after a number of years, taking possession of another form and living in that. Who can admit such continuity of life for the insect and deny it for man? Can there be a deathless something in a worm and not in a human being? Even without the mass of physical evidence that exists upon the subject the logic of nature would lead us to confident conclusions. The knowledge of evolution which science has so far accumulated leads to four natural inferences. One is that man is immortal. Another is that he has, like all creatures, slowly evolved to what he now is. A third is that both life, and the forms it uses, are evolving together, and the fourth is that lower orders evolve into higher and continually higher ones. The human soul evolves from the savage to the saint--from animal instincts to the self-sacrifice of martyrs and heroes. We cannot escape the conclusion that the race has evolved, is evolving and will continue to evolve until mental and moral perfection has been attained. If neither the theory of the materialist nor the popular notion that the soul is created at birth is satisfactory, we have only reincarnation left as a working hypothesis; and if we accept the evolution of the soul as a natural truth, then reincarnation becomes a necessity in explaining the known facts of life. But there are some students of life who appear to refuse the hypothesis of reincarnation while wishing to accept the idea of the evolution of the soul. But how would that be possible? If the soul is evolving it is under the necessity of developing by the laws of growth. They were discussed in Chapter IX. Those who desire to put their ideas about the soul and its immortality into harmony with the facts of evolution sometimes ask why it would not be possible for the soul to leave the material plane forever at the death of the physical body and then pursue its evolution on higher planes. In the vast universe there must be opportunity for all possible development, it is argued. But why go on into other regions when the lessons here have not been learned? That would be a violation of nature's law of the conservation of energy. The average human being is in the elementary grades, with scores of incarnations ahead of him before he will be in a position even to take advantage of his opportunities and thus make fairly rapid progress. To talk of going on to higher planes for further evolution is like proposing that a child shall leave the kindergarten and enter the university.