The Unseen World and Other Essays | Page 5

such
extraordinary events there was endless room for guesswork; but the
discovery of natural selection was the discovery of a process, going on
perpetually under our very eyes, which must inevitably of itself
extinguish some species and bring new ones into being. In these and
countless other ways we have learned that all the rich variety of nature
is pervaded by unity of action, such as we might expect to find if nature
is the manifestation of an infinite God who is without variableness or
shadow of turning, but quite incompatible with the fitful behaviour of
the anthropomorphic deities of the old mythologies. By thus abstaining
from all appeal to agencies that are extra-cosmic, or not involved in the

orderly system of events that we see occurring around us, we have at
last succeeded in eliminating from philosophic speculation the
character of random guesswork which at first of necessity belonged to
it. Modern scientific hypothesis is so far from being a haphazard mental
proceeding that it is perhaps hardly fair to classify it with guesses. It is
lifted out of the plane of guesswork, in so far as it has acquired the
character of inevitable inference from that which now is to that which
has been or will be. Instead of the innumerable particular assumptions
which were once admitted into cosmic philosophy, we are now reduced
to the one universal assumption which has been variously described as
the "principle of continuity," the "uniformity of nature," the
"persistence of force," or the "law of causation," and which has been
variously explained as a necessary datum for scientific thinking or as a
net result of all induction. I am not unwilling, however, to adopt the
language of a book which has furnished the occasion for the present
discussion, and to say that this grand assumption is a supreme act of
faith, the definite expression of a trust that the infinite Sustainer of the
universe "will not put us to permanent intellectual confusion." For in
this mode of statement the harmony between the scientific and the
religious points of view is well brought out. It is as affording the only
outlet from permanent intellectual confusion that inquirers have been
driven to appeal to the principle of continuity; and it is by unswerving
reliance upon this principle that we have obtained such insight into the
past, present, and future of the world as we now possess.
The work just mentioned[1] is especially interesting as an attempt to
bring the probable destiny of the human soul into connection with the
modern theories which explain the past and future career of the
physical universe in accordance with the principle of continuity. Its
authorship is as yet unknown, but it is believed to be the joint
production of two of the most eminent physicists in Great Britain, and
certainly the accurate knowledge and the ingenuity and subtlety of
thought displayed in it are such as to lend great probability to this
conjecture. Some account of the argument it contains may well precede
the suggestions presently to be set forth concerning the Unseen World;
and we shall find it most convenient to begin, like our authors, with a
brief statement of what the principle of continuity teaches as to the

proximate beginning and end of the visible universe. I shall in the main
set down only results, having elsewhere[2] given a simple exposition of
the arguments upon which these results are founded.
[1] The Unseen Universe; or, Physical Speculations on a Future State.
[Attributed to Professors TAIT and BALFOUR STEWART.] New
York: Macmillan & Co. 1875. 8vo. pp. 212.
[2] Outlines of Cosmic Philosophy, based on the Doctrine of Evolution.
Boston: J. R. Osgood & Co. 1875. 2 vols. 8vo.
The first great cosmological speculation which has been raised quite
above the plane of guesswork by making no other assumption than that
of the uniformity of nature, is the well-known Nebular Hypothesis.
Every astronomer knows that the earth, like all other cosmical bodies
which are flattened at the poles, was formerly a mass of fluid, and
consequently filled a much larger space than at present. It is further
agreed, on all hands, that the sun is a contracting body, since there is no
other possible way of accounting for the enormous quantity of heat
which he generates. The so-called primeval nebula follows as a
necessary inference from these facts. There was once a time when the
earth was distended on all sides away out to the moon and beyond it, so
that the matter now contained in the moon was then a part of our
equatorial zone. And at a still remoter date in the past, the mass of the
sun was diffused in every direction beyond the orbit of Neptune, and no
planet had an individual existence, for all