9. A single corporeal existence is manifestly insufficient to enable a spirit to acquire all the goodness it lacks, and rid itself of all the evil that is within it. Would it be possible, for an instant, for a savage to attain, in a single incarnation, to the intellectual and moral level of the most advanced European? It is physically impossible for the savage to do so. Must such a one as this, then, remain eternally in ignorance and barbarism, deprived of the enjoyments that can only be reached through the development of the intellectual and moral faculties? The simplest common sense suffices to show us that such a supposition would be the negation, both of the justice and goodness of God and of the law of progress, which is the law of nature. And it is for this reason that God, being supremely just and good, grants to the spirit of each human being as many successive existences as are needed for attaining to the perfection which is the aim of all.
In each new existence, a spirit brings with it, under the form of natural aptitudes, of intuitive knowledge, of intelligence, and of morality, all the gains that have been made by it in its previous existences. Thus each new existence takes it a step further upon the road of progress. *
Incarnation is inherent to the inferior condition of the spirit. It is no longer necessary when inferiority is overcome and there is continued progress in the spiritual state or in the physical existences of more advanced worlds that do not maintain earthly materialization.
* See footnote, Chap. I., no. 2