er needed. These forms have a much longer lease of
Life. And it may be taken as a rule, although it has exceptions, that
complexity in animal organisms is always associated with longevity.

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