Charles Darwin also tells us that Heredity and Environment are the prime influences under which the whole Organic World is sustained; in other words, every organism has implanted in it by heredity the principle of life, but the conditions under which it will be possible for that life to expand and come to perfection, rest entirely upon its power to bring itself into harmony with its environment. This principle of life does not come naked into the world, it is fortified by heredity, with power gained by its parents in their struggle for existence, and in their persistence to get into sympathy with their environment. The knowledge they gained, by this struggle, they have handed down to their offspring, and given it thereby the possibility of also gaining for itself that knowledge of, and power to get into sympathy with, its environment, upon which its future existence will depend. So may we not see that in the Spiritual World, these two conditions dominate, and that it is only by the clear comprehension of their reality that we can understand how all-important it is for the soul to bring itself nearer and nearer into harmony with its environment, the Spiritual, and how the efficacy of prayer depends upon the Knowledge of what is the Will of God? We have received from our Spiritual Father the principle of Everlasting Life, and the aspirations which, if followed, will enable that life to expand and come to perfection; but, as in the case of physical organism, the gift is useless unless we elect to use those aspirations aright, and gain thereby a knowledge of our Spiritual Environment, which alone can bring us into sympathy with the Great Reality. Without this "Knowledge of God," we can see by analogy on the Organic Plane that Everlasting Life is impossible--we are as weeds and shall be rooted out. This is no figment of the imagination, it seems to be the only conclusion we can come to if Nature is the work of Nature's God, and Man is made in the image (spiritual) of that God. Herbert Spencer came to the same conclusion when defining everlasting existence. He says: "Perfect correspondence would be perfect life; were there no changes in the environment but such as the organism had adapted changes to meet, and were it never to fail in the efficiency with which it met them, there would be Eternal Existence and Eternal Knowledge" (_Principles of Biology_).