would
have been avoided. It is just as essential at the present moment to
insist on the point as ever. But to proceed. Stated in the extreme
form, the theory is, that given matter as a beginning, that matter is
thenceforth capable, by the aid of fixed and self-working laws, to
produce and result in, all the phenomena of life--whether plant, animal,
or human--which we see around us. Matter developes from simple to
complex forms, growing by its own properties, in directions determined
by the circumstances and surroundings of its existence.

[Footnote 1: It is enough to instance the theories of Dr. Buchner and,
in earlier days, of Oken. The Haeckel and Virchow incident in this
connection, and the noble protest of the latter against positive
teaching of unproved speculation, are in the recollection of all.]

If I may put this a little less in the abstract, but more at length, I
should describe it thus[1]:--

Astronomers, while watching the course of the stars, have frequently
observed in the heavens what they call _nebulae_. With the best
telescopes these look like patches of gold-dust or luminous haze in the
sky. Some nebulae, it is supposed, really consist of whole systems of
stars and suns, but at so enormous a distance that with our best glasses
we cannot make more out of them than groups of apparent "star-dust" But
other nebulae do not appear to be at this extreme distance, and therefore
cannot consist of large bodies. And when their light is examined with
the aid of a spectroscope, it gives indications that such nebulae are
only masses of vapour, incandescent, or giving out light on account of
their being in a burning or highly heated condition.

[Footnote 1: The biological evolutionist will, I am aware, object to
this, saying that the origin of the cosmos and nebular theories are
matters of speculation with which he is not concerned--they are no part
of evolution proper. But I submit that the general philosophical
evolution does include the whole. At any rate, the materialist view of
nature does take in the whole, in such a way as the text indicates.]

Now, it is supposed that, in the beginning of the world, there was, in
space, such a nebula or mass of incandescent vapour, which, as it was
destined to cool down and form a world, philosophers have called "cosmic
gas."

This cosmic gas, in the course of time, began to lose its heat, and
consequently to liquefy and solidify, according to the different nature