d? To such a being I can imagine not only the vegetable, but
the mineral world, responsive to the proper irritants, the response
differing only in degree from those exaggerated manifestations, which,
in virtue of their magnitude, appeal to our weak powers of
observation.

Our conclusion, however, must be based, not on powers that we imagine,
but upon those that we possess. What do they reveal? As the earth
and atmosphere offer themselves as the nutriment of the vegetable
world, so does the latter, which contains no constituent not found in
inorganic nature, offer itself to the animal world. Mixed with
certain inorganic substances--water, for example--the vegetable
constitutes, in the long run, the sole sustenance of the animal.
Animals may be divided into two classes, the first of which can
utilise the vegetable world immediately, having chemical forces strong
enough to cope with its most refractory parts; the second class use
the vegetable world mediately; that is to say, after its finer
portions have been extracted and stored up by the first. But in
neither class have we an atom newly created. The animal world is, so
to say, a distillation through the vegetable world from inorganic
nature.

From this point of view all three worlds would constitute a unity, in
which I picture life as immanent everywhere. Nor am I anxious to shut
out the idea that the life here spoken of, may be but a subordinate
part and function of a Higher Life, as the living moving blood is
subordinate to the living man. I resist no such idea as long as it is
not dogmatically imposed. Left for the human mind freely to operate
upon, the idea has ethical vitality; but, stiffened into a dogma, the
inner force disappears, and the outward yoke of a usurping hierarchy
takes its place.

The problem before us is, at all events, capable of definite
statement. We have on the one hand strong grounds for concluding that
the earth was once a molten mass. We now find it not only swathed by
an atmosphere, and covered by a sea, but also crowded with living
things. The question is, How were they introduced? Certainty may be
as unattainable here as Bishop Butler held it to be in matters of
religion; but in the contemplation of probabilities the thoughtful
mind is forced to take a side. The conclusion of Science, which
recognises unbroken causal connection between the past and the
present, would undoubtedly be that the molten earth contained within
i