_The Rapid Growth of Modern Knowledge._
At no time since men have dwelt upon the earth have their notions about
the universe undergone so great a change as in the century of which we
are now approaching the end. Never before has knowledge increased so
rapidly; never before has philosophical speculation been so actively
conducted, or its results so widely diffused. It is a characteristic
of organic evolution that numerous progressive tendencies, for a long
time inconspicuous, now and then unite to bring about a striking and
apparently sudden change; or a set of forces, quietly accumulating
in one direction, at length unlock some new reservoir of force and
abruptly inaugurate a new series of phenomena, as when water rises in
a tank until its overflow sets whirling a system of toothed wheels.
It may be that Nature makes no leaps, but in this way she now and then
makes very long strides. It is in this way that the course of organic
development is marked here and there by memorable epochs, which seem
to open new chapters in the history of the universe. There was such
an epoch when the common ancestor of ascidian and amphioxus first
showed rudimentary traces of a vertebral column. There was such an
epoch when the air-bladder of early amphibians began to do duty as a
lung. Greatest of all, since the epoch, still hidden from our ken,
when organic life began upon the surface of the globe, was the birth
of that new era when, through a wondrous change in the direction of
the working of natural selection, Humanity appeared upon the scene.
In the career of the human race we can likewise point to periods in
which it has become apparent that an immense stride was taken. Such a
period marks the dawning of human history, when after countless ages
of desultory tribal warfare men succeeded in uniting into comparatively
stable political societies, and through the medium of written language
began handing down to posterity the record of their thoughts and
deeds. Since that morning twilight of history there has been no era
so strongly marked, no change so swift or so far-reaching in the
conditions of human life, as that which began with the great maritime
discoveries of the fifteenth century and is approaching its culmination
to-day. In its earlier stages this modern era was signalized by
sporadic achievements of the human intellect, great in themselves and
leading to such stupendous results as the boldest dared not dream of.
Such achievements were the invention of printing, the telescope and
microscope, the geometry of Descartes, the astronomy of Newton, the
physics of Huyghens, the physiology of Harvey. Man's senses were thus
indefinitely enlarged as his means of registration were perfected; he
became capable of extending physical inferences from the earth to the
heavens; and he made his first acquaintance with that luminiferous
ether which was by and by to reveal the intimate structure of matter in
regions far beyond the power of the microscope to penetrate.
It is only within the present century that the vastness of the changes
thus beginning to be wrought has become apparent. The scientific
achievements of the human intellect no longer occur sporadically: they
follow one upon another, like the organized and systematic conquests
of a resistless army. Each new discovery becomes at once a powerful
implement in the hands of innumerable workers, and each year wins over
fresh regions of the universe from the unknown to the known. Our own
generation has become so wonted to this unresting march of discovery
that we already take it as quite a matter of course. Our minds become
easily deadened to its real import, and the examples we cite in
illustration of it have an air of triteness. We scarcely need to be
reminded that all the advances made in locomotion, from the days of
Nebuchadnezzar to those of Andrew Jackson, were as nothing compared to
the change that has been wrought within a few years by the introduction
of railroads. In these times, when Puck has fulfilled his boast and put
a girdle about the earth in forty minutes, we are not yet perhaps in
danger of forgetting that a century has not elapsed since he who caught
the lightning upon his kite was laid in the grave. Yet the lesson of
these facts, as well as of the grandmother's spinning-wheel that stands
by the parlour fireside, is well to bear in mind. The change therein
exemplified since Penelope plied her distaff is far less than that
which has occurred within the memory of living men. The developments
of machinery, which have worked such wonders, have greatly altered the
political conditions of human society, so that a huge republic like
the United States is now as snug and compact and easily manageable
as the tiny republic of Switzerland in the eighteenth century. The
number of men that can live upon a given area of the earth's surface
has been multiplied manifold, and while the mass of human life has thus
increased its value has been at the same time enhanced.
In these various applications of physical theory to the industrial
arts, countless minds, of a class that formerly were not reached
by scientific reasoning at all, are now brought into daily contact
with complex and subtle operations of matter, and their habits of
thought are thus notably modified. Meanwhile, in the higher regions
of chemistry and molecular physics the progress has been such that
no description can do it justice. When we reflect that a fourth
generation has barely had time to appear on the scene since Priestley
discovered that there was such a thing as oxygen, we stand awestruck
before the stupendous pile of chemical science which has been reared
in this brief interval. Our knowledge thus gained of the molecular
and atomic structure of matter has been alone sufficient to remodel
our conceptions of the universe from beginning to end. The case of
molecular physics is equally striking. The theory of the conservation
of energy, and the discovery that light, heat, electricity, and
magnetism are differently conditioned modes of undulatory motion
transformable each into the other, are not yet fifty years old. In
physical astronomy we remained until 1839 confined within the limits of
the solar system, and even here the Newtonian theory had not yet won
its crowning triumph in the discovery of the planet Neptune. To-day
we not only measure the distances and movements of many stars, but by
means of spectrum analysis are able to tell what they are made of.
It is more than a century since the nebular hypothesis, by which we
explain the development of stellar systems, was first propounded by
Immanuel Kant, but it is only within thirty years that it has been
generally adopted by astronomers; and among the outward illustrations
of its essential soundness none is more remarkable than its surviving
such an enlargement of our knowledge. Coming to the geologic study
of the changes that have taken place on the earth's surface, it was
in 1830 that Sir Charles Lyell published the book which first placed
this study upon a scientific basis. Cuvier's classification of past
and present forms of animal life, which laid the foundations alike of
comparative anatomy and of palæontology, came but little earlier. The
cell-doctrine of Schleiden and Schwann, prior to which modern biology
can hardly be said to have existed, dates from 1839; and it was only
ten years before that the scientific treatment of embryology began with
Von Baer. At the present moment, twenty-six years have not elapsed
since the epoch-making work of Darwin first announced to the world the
discovery of natural selection.
In the cycle of studies which are immediately concerned with the career
of mankind, the rate of progress has been no less marvellous. The
scientific study of human speech may be said to date from the flash
of insight which led Friedrich Schlegel in 1808 to detect the kinship
between the Aryan languages. From this beginning to the researches of
Fick and Ascoli in our own time, the quantity of achievement rivals
anything the physical sciences can show. The study of comparative
mythology, which has thrown such light upon the primitive thoughts
of mankind, is still younger,--is still, indeed, in its infancy. The
application of the comparative method to the investigation of laws
and customs, of political and ecclesiastical and industrial systems,
has been carried on scarcely thirty years; yet the results already
obtained are obliging us to rewrite the history of mankind in all its
stages. The great achievements of archæologists--the decipherment
of Egyptian hieroglyphs and of cuneiform inscriptions in Assyria
and Persia, the unearthing of ancient cities, the discovery and
classification of primeval implements and works of art in all quarters
of the globe--belong almost entirely to the nineteenth century. These
discoveries, which have well-nigh doubled for us the length of the
historic period, have united with the quite modern revelations of
geology concerning the ancient glaciation of the temperate zones, to
give us an approximate idea of the age of the human race[1] and the
circumstances attending its diffusion over the earth. It has thus at
length become possible to obtain something like the outlines of a
comprehensive view of the history of the creation, from the earliest
stages of condensation of our solar nebula down to the very time in
which we live, and to infer from the characteristics of this past
evolution some of the most general tendencies of the future.
All this accumulation of physical and historical knowledge has not
failed to react upon our study of the human mind itself. In books of
logic the score of centuries between Aristotle and Whately saw less
advance than the few years between Whately and Mill. In psychology the
work of Fechner and Wundt and Spencer belongs to the age in which we
are now living. When to all this variety of achievement we add what has
been done in the critical study of literature and art, of classical
and Biblical philology, and of metaphysics and theology, illustrating
from fresh points of view the history of the human mind, the sum total
becomes almost too vast to be comprehended. This century, which some
have called an age of iron, has been also an age of ideas, an era of
seeking and finding the like of which was never known before. It is
an epoch the grandeur of which dwarfs all others that can be named
since the beginning of the historic period, if not since Man first
became distinctively human. In their mental habits, in their methods
of inquiry, and in the data at their command, "the men of the present
day who have fully kept pace with the scientific movement are separated
from the men whose education ended in 1830 by an immeasurably wider
gulf than has ever before divided one progressive generation of men
from their predecessors."[2] The intellectual development of the human
race has been suddenly, almost abruptly, raised to a higher plane
than that upon which it had proceeded from the days of the primitive
troglodyte to the days of our great-grandfathers. It is characteristic
of this higher plane of development that the progress which until
lately was so slow must henceforth be rapid. Men's minds are becoming
more flexible, the resistance to innovation is weakening, and our
intellectual demands are multiplying while the means of satisfying
them are increasing. Vast as are the achievements we have just passed
in review, the gaps in our knowledge are immense, and every problem
that is solved but opens a dozen new problems that await solution.
Under such circumstances there is no likelihood that the last word will
soon be said on any subject. In the eyes of the twenty-first century
the science of the nineteenth will doubtless seem very fragmentary
and crude. But the men of that day, and of all future time, will no
doubt point back to the age just passing away as the opening of a
new dispensation, the dawning of an era in which the intellectual
development of mankind was raised to a higher plane than that upon
which it had hitherto proceeded.
As the inevitable result of the thronging discoveries just enumerated,
we find ourselves in the midst of a mighty revolution in human thought.
Time-honoured creeds are losing their hold upon men; ancient symbols
are shorn of their value; everything is called in question. The
controversies of the day are not like those of former times. It is
no longer a question of hermeneutics, no longer a struggle between
abstruse dogmas of rival churches. Religion itself is called upon to
show why it should any longer claim our allegiance. There are those
who deny the existence of God. There are those who would explain
away the human soul as a mere group of fleeting phenomena attendant
upon the collocation of sundry particles of matter. And there are
many others who, without committing themselves to these positions of
the atheist and the materialist, have nevertheless come to regard
religion as practically ruled out from human affairs. No religious
creed that man has ever devised can be made to harmonize in all its
features with modern knowledge. All such creeds were constructed
with reference to theories of the universe which are now utterly and
hopelessly discredited. How, then, it is asked, amid the general wreck
of old beliefs, can we hope that the religious attitude in which from
time immemorial we have been wont to contemplate the universe can any
longer be maintained? Is not the belief in God perhaps a dream of the
childhood of our race, like the belief in elves and bogarts which once
was no less universal? and is not modern science fast destroying the
one as it has already destroyed the other?
Such are the questions which we daily hear asked, sometimes with
flippant eagerness, but oftener with anxious dread. In view of them
it is well worth while to examine the idea of God, as it has been
entertained by mankind from the earliest ages, and as it is affected by
the knowledge of the universe which we have acquired in recent times.
If we find in that idea, as conceived by untaught thinkers in the
twilight of antiquity, an element that still survives the widest and
deepest generalizations of modern times, we have the strongest possible
reason for believing that the idea is permanent and answers to an
Eternal Reality. It was to be expected that conceptions of Deity handed
down from primitive men should undergo serious modification. If it can
be shown that the essential element in these conceptions must survive
the enormous additions to our knowledge which have distinguished the
present age above all others since man became man, then we may believe
that it will endure so long as man endures; for it is not likely that
it can ever be called upon to pass a severer ordeal.
All this will presently appear in a still stronger light, when we have
set forth the common characteristic of the modifications which the idea
of God has already undergone, and the nature of the opposition between
the old and the new knowledge with which we are now confronted. Upon
this discussion we have now to enter, and we shall find it leading
us to the conclusion that throughout all possible advances in human
knowledge, so far as we can see, the essential position of theism must
remain unshaken.