IT may be safely assumed that, two thousand years ago, before Caesar
set foot in southern Britain, the whole country-side visible from the
windows of the room in which I write, was in what is called "the state
of nature." Except, it may be, by raising a few sepulchral mounds,
such as those which still, here and there, break the flowing contours
of the downs, man's hands had made no mark upon it; and the thin veil
of vegetation which overspread the broad-backed heights and the
shelving sides of the coombs was unaffected by his industry. The
native grasses and weeds, the scattered patches of gorse, contended
with one another for the possession of the scanty surface soil; they
fought against the droughts of summer, the frosts of winter, and the
furious gales which swept, with unbroken force, now from the [2]
Atlantic, and now from the North Sea, at all times of the year; they
filled up, as they best might, the gaps made in their ranks by all
sorts of underground and overground animal ravagers. One year with
another, an average population, the floating balance of the unceasing
struggle for existence among the indigenous plants, maintained itself.
It is as little to be doubted, that an essentially similar state of
nature prevailed, in this region, for many thousand years before the
coming of Caesar; and there is no assignable reason for denying that
it might continue to exist through an equally prolonged futurity,
except for the intervention of man.
Reckoned by our customary standards of duration, the native vegetation,
like the "everlasting hills" which it clothes, seems a type of
permanence. The little Amarella Gentians, which abound in some places
to-day, are the descendants of those that were trodden underfoot, by
the prehistoric savages who have left their flint tools, about, here
and there; and they followed ancestors which, in the climate of the
glacial epoch, probably flourished better than they do now. Compared
with the long past of this humble plant, all the history of civilized
men is but an episode.
Yet nothing is more certain than that, measured by the liberal scale
of time-keeping of the universe, this present state of nature, however
it may seem to have gone and to go on for ever, is [3] but a fleeting
phase of her infinite variety; merely the last of the series of
changes which the earth's surface has undergone in the course of the
millions of years of its existence. Turn back a square foot of the
thin turf, and the solid foundation of the land, exposed in cliffs of
chalk five hundred feet high on the adjacent shore, yields full
assurance of a time when the sea covered the site of the "everlasting
hills"; and when the vegetation of what land lay nearest, was as
different from the present Flora of the Sussex downs, as that of
Central Africa now is.* No less certain is it that, between the time
during which the chalk was formed and that at which the original turf
came into existence, thousands of centuries elapsed, in the course of
which, the state of nature of the ages during which the chalk was
deposited, passed into that which now is, by changes so slow that, in
the coming and going of the generations of men, had such witnessed
them, the contemporary conditions would have seemed to be unchanging
and unchangeable.
* See "On a piece of Chalk" in the preceding volume of these
Essays (vol. viii. p. 1).
But it is also certain that, before the deposition of the chalk, a
vastly longer period had elapsed; throughout which it is easy to
follow the traces of the same process of ceaseless modification and of
the internecine struggle for existence of living things; and that even
when we can get no further [4] back, it is not because there is any
reason to think we have reached the beginning, but because the trail
of the most ancient life remains hidden, or has become obliterated.
Thus that state of nature of the world of plants which we began by
considering, is far from possessing the attribute of permanence. Rather
its very essence is impermanence. It may have lasted twenty or thirty
thousand years, it may last for twenty or thirty thousand years more,
without obvious change; but, as surely as it has followed upon a very
different state, so it will be followed by an equally different
condition. That which endures is not one or another association of
living forms, but the process of which the cosmos is the product, and
of which these are among the transitory expressions. And in the living
world, one of the most characteristic features of this cosmic process
is the struggle for existence, the competition of each with all, the
result of which is the selection, that is to say, the survival of
those forms which, on the whole, are best adapted, to the conditions
which at any period obtain; and which are, therefore, in that respect,
and only in that respect, the fittest.* The acme reached by the cosmic
[5] process in the vegetation of the downs is seen in the turf, with
its weeds and gorse. Under the conditions, they have come out of the
struggle victorious; and, by surviving, have proved that they are the
fittest to survive.
* That every theory of evolution must be consistent not merely
with progressive development, but with indefinite persistence
in the same condition and with retrogressive modification, is a
point which I have insisted upon repeatedly from the year 1862
till now. See Collected Essays, vol. ii. pp. 461-89; vol. iii.
p. 33; vol. viii. p. 304. In the address on "Geological
Contemporaneity and Persistent Types" (1862), the
paleontological proofs of this proposition were, I believe,
first set forth.
That the state of nature, at any time, is a temporary phase of a
process of incessant change, which has been going on for innumerable
ages, appears to me to be a proposition as well established as any in
modern history.
Paleontology assures us, in addition, that the ancient philosophers
who, with less reason, held the same doctrine, erred in supposing that
the phases formed a cycle, exactly repeating the past, exactly
foreshadowing the future, in their rotations. On the contrary, it
furnishes us with conclusive reasons for thinking that, if every link
in the ancestry of these humble indigenous plants had been preserved
and were accessible to us, the whole would present a converging series
of forms of gradually diminishing complexity, until, at some period in
the history of the earth, far more remote than any of which organic
remains have yet been discovered, they would merge in those low groups
among which the Boundaries between animal and vegetable life become
effaced.*
* "On the Border Territory between the Animal and the Vegetable
Kingdoms," Essays, vol. viii. p. 162
[6] The word "evolution," now generally applied to the cosmic process,
has had a singular history, and is used in various senses.* Taken in
its popular signification it means progressive development, that is,
gradual change from a condition of relative uniformity to one of
relative complexity; but its connotation has been widened to include
the phenomena of retrogressive metamorphosis, that is, of progress
from a condition of relative complexity to one of relative uniformity.
As a natural process, of the same character as the development of a
tree from its seed, or of a fowl from its egg, evolution excludes
creation and all other kinds of supernatural intervention. As the
expression of a fixed order, every stage of which is the effect of
causes operating according to definite rules, the conception of
evolution no less excludes that of chance. It is very desirable to
remember that evolution is not an explanation of the cosmic process,
but merely a generalized statement of the method and results of that
process. And, further, that, if there is proof that the cosmic process
was set going by any agent, then that agent will be, the creator of it
and of all its products, although supernatural intervention may remain
strictly excluded from its further course.
So far as that limited revelation of the nature of things, which we
call scientific knowledge, has [7] yet gone, it tends, with constantly
increasing emphasis, to the belief that, not merely the world of
plants, but that of animals; not merely living things, but the whole
fabric of the earth; not merely our planet, but the whole solar
system; not merely our star and its satellites, but the millions of
similar bodies which bear witness to the order which pervades
boundless space, and has endured through boundless time; are all
working out their predestined courses of evolution.
* See "Evolution in Biology," Essays, vol. ii. p. 187
With none of these have I anything to do, at present, except with that
exhibited by the forms of life which tenant the earth. All plants and
animals exhibit the tendency to vary, the causes of which have yet to
be ascertained; it is the tendency of the conditions of life, at any
given time, while favouring the existence of the variations best
adapted to them, to oppose that of the rest and thus to exercise
selection; and all living things tend to multiply without limit, while
the means of support are limited; the obvious cause of which is the
production of offspring more numerous than their progenitors, but with
equal expectation of life in the actuarial sense. Without the first
tendency there could be no evolution. Without the second, there would
be no good reason why one variation should disappear and another take
its place; that is to say there would be no selection. Without the [8]
third, the struggle for existence, the agent of the selective process
in the state of nature, would vanish.*
* Collected Essays, vol. ii. passim.
Granting the existence of these tendencies, all the known facts of the
history of plants and of animals may be brought into rational
correlation. And this is more than can be said for any other
hypothesis that I know of. Such hypotheses, for example, as that of
the existence of a primitive, orderless chaos; of a passive and
sluggish eternal matter moulded, with but partial success, by
archetypal ideas; of a brand-new world-stuff suddenly created and
swiftly shaped by a supernatural power; receive no encouragement, but
the contrary, from our present knowledge. That our earth may once have
formed part of a nebulous cosmic magma is certainly possible, indeed
seems highly probable; but there is no reason to doubt that order
reigned there, as completely as amidst what we regard as the most
finished works of nature or of man.** The faith which is born of
knowledge, finds its object in an eternal order, bringing forth
ceaseless change, through endless time, in endless space; the
manifestations of the cosmic energy alternating between phases of
potentiality and phases of explication. It may be that, as Kant
suggests,*** every cosmic [9] magma predestined to evolve into a new
world, has been the no less predestined end of a vanished predecessor.
**Ibid., vol. iv. p. 138; vol. v. pp. 71-73.
***Ibid., vol. viii. p. 321.