s the
conception of life as a something which works through matter, but is
independent of it; and even those who are aware that matter and life are
inseparably connected may not be prepared for the conclusion--plainly
suggested by the phrase, "_the_ physical basis or matter of life,"--that
there is some one kind of matter which is common to all living beings, and
that their endless diversities are bound together by a physical, as well
as an ideal, unity. In fact, when first apprehended, such a doctrine as
this appears almost shocking to common sense.

What, truly, can seem to be more obviously different from one another, in
faculty, in form, and in substance, than the various kinds of living
beings? What community of faculty can there be between the brightly
colored lichen, which so nearly resembles a mere mineral incrustation of
the bare rock on which it grows, and the painter, to whom it is instinct
with beauty, or the botanist, whom it feeds with knowledge?

Again, think of the microscopic fungus--a mere infinitesimal ovoid
particle, which finds space and duration enough to multiply into countless
millions in the body of a living fly; and then of the wealth of foliage,
the luxuriance of flower and fruit, which lies between this bald sketch
of a plant and the giant pine of California, towering to the dimensions of
a cathedral spire, or the Indian fig, which covers acres with its profound
shadow, and endures while nations and empires come and go around its vast
circumference. Or, turning to the other half of the world of life, picture
to yourselves the great Finner whale, hugest of beasts that live or have
lived, disporting his eighty or ninety feet of bone, muscle, and blubber,
with easy roll, among waves in which the stoutest ship that ever left
dockyard would founder hopelessly; and contrast him with the invisible
animalcules--mere gelatinous specks, multitudes of which could, in fact,
dance upon the point of a needle with the same ease as the angels of the
Schoolmen could, in imagination. With these images before your minds, you
may well ask, what community of form, or structure, is there between the
animalcule and the whale, or between the fungus and the fig tree? And, _a
fortiori_, between all four?

Finally, if we regard substance, or material composition, what hidden bond
can connect the flower that a girl wears in her hair and the blood that
courses through her youthful veins; or, what is there in common betw