It may be objected that these illustrations are taken merely from morbid conditions. But whether the Life be cut short by accident or by disease the principle is the same. All dissolution is brought about practically in the same way. A certain condition in the Environment fails to be met by a corresponding condition in the organism, and this is death. And conversely the more an organism in virtue of its complexity can adapt itself to all the parts of its Environment, the longer it will live. "It is manifest _a priori_," says Mr. Herbert Spencer, "that since changes in the physical state of the environment, as also those mechanical actions and those variations of available food which occur in it, are liable to stop the processes going on in the organism; and since the adaptive changes in the organism have the effects of directly or indirectly counterbalancing these changes in the environment, it follows that the life of the organism will be short or long, low or high, according to the extent to which changes in the environment are met by corresponding changes in the organism. Allowing a margin for perturbations, the life will continue only while the correspondence continues; the completeness of the life will be proportionate to the completeness of the correspondence; and the life will be perfect only when the correspondence is perfect." [1] [1] "Principles of Biology," p. 82. We are now all but in sight of our scientific definition of Eternal Life. The desideratum is an organism with a correspondence of a very exceptional kind. It must lie beyond the reach of those "mechanical actions" and those "variations of available food," which are "liable to stop the processes going on in the organism." Before we reach an Eternal Life we must pass beyond that point at which all ordinary correspondences inevitably cease. We must find an organism so high and complex, that at some point in its development it shall have added a correspondence which organic death is powerless to arrest. We must, in short, pass beyond that finite region where the correspondences depend on evanescent and material media, and enter a further region where the Environment corresponded with is itself Eternal. Such an Environment exists. The Environment of the Spiritual world is outside the influence of these "mechanical actions," which sooner or later interrupt the processes going on in all finite organisms. If then we can find an organism which has established a correspondence with the spiritual world, that correspondence will possess the elements of eternity-- provided only one other condition be fulfilled.