THE DEVELOPMENT OF THE IDEA OF EVOLUTION TO THE INORGANIC WORLD
We have seen in the preceding chapter that, with respect to the origin
of plants and animals--including man himself--two very distinct lines of
speculation have arisen; these two lines of thought may be expressed by
the terms 'manufacture'--literally making by hand, and 'development' or
'evolution,'--a gradual unfolding from simpler to more complex forms.
Now with respect to the _inorganic_ world two parallel hypotheses of
'creation' have arisen, like those relating to _organic_ nature; but in
the former case the determining factor in the choice of ideas has been,
not the avocations of the primitive peoples, but the nature of their
surroundings.
The dwellers in the valleys of the Euphrates and Tigris could not but be
impressed by the great and destructive floods to which those regions
were subject; and the inhabitants of the shores and islands of the
Aegean Sea, and of the Italian peninsula, were equally conversant with
the devastations wrought by volcanic outbursts and earthquake shocks. As
great districts were seen to be depopulated by these catastrophies,
might not some even more violent cataclysm of the same kind actually
destroy all mankind, with the animals and plants, in the comparatively
small area then known as 'the world'? The great flood, of which all
these nations appear to have retained traditions, was regarded as only
the last of such destructive cataclysms; and, in this way, there
originated the myth of successive destructions of the face of the earth,
each followed by the creation of new stocks of plants and animals. This
is the doctrine now known as 'Catastrophism,' which we find prevalent in
the earliest traditions and writings of India, Babylonia, Syria and
Greece.
But in ancient Egypt quite another class of phenomena was conspicuously
presented to the early philosophers of the country. Instead of sudden
floods and terrible displays of volcanic and earthquake violence, they
witnessed the annual gentle rise and overflowings of their grand river,
with its beneficent heritage of new soil; and they soon learned to
recognise that Egypt itself--so far as the delta was concerned--was 'the
gift of the Nile.'
From the contemplation of these phenomena, the Egyptian sages were
gradually led to entertain the idea that all the features of the
earth--as they knew it--might have been similarly produced through the
slow and constant action of the causes now seen in operation around
them. This idea was incorporated in a myth, which was suggested by the
slow and gradual transformation of an egg into a perfect, growing
organism. The birth of the world was pictured as an act of incubation,
and male and female deities were invented to play the part of parents to
the infant world. By Pythagoras, who resided for more than twenty years
in Egypt, these ideas were introduced to the Greek philosophers, and
from that time 'Catastrophism' found a rival in the new doctrine which
we shall see has been designated under the names of 'Continuity,'
'Uniformitarianism' or 'Evolution.' How, from the first crude notions of
evolution, successive thinkers developed more just and noble conceptions
on the subject, has been admirably shown by Professor Osborn in his
_From the Greeks to Darwin_ and by Mr Clodd in his _Pioneers of
Evolution_.
Poets, from Empedocles and Lucretius to Goethe and Tennyson, have sought
in their verses to illustrate the beauty of evolutionary ideas; and
philosophers, from Aristotle and Strabo to Kant and Herbert Spencer,
have recognised the principle of evolution as harmonising with, and
growing out of, the highest conceptions of science. Yet it was not till
the Nineteenth Century that any serious attempts were made to establish
the hypothesis of evolution as a definite theory, based on sound
reasoning from careful observation.
It is true that there were men, in advance of their age, who in some
cases anticipated to a certain extent this work of establishing the
doctrine of evolution on a firm foundation. Thus in Italy, the earliest
home of so many sciences, a Carmelite friar, Generelli, reasoning on
observations made by his compatriots Fracastoro and Leonardo da Vinci in
the Sixteenth Century, Steno and Scilla in the Seventeenth, and Lazzaro
Moro and Marsilli in the Eighteenth Century, laid the foundations of a
rational system of geology in a work published in 1749 which was
characterised alike by courage and eloquence. In France, the illustrious
Nicolas Desmarest, from his study of the classical region of the
Auvergne, was able to show, in 1777, how the river valleys of that
district had been carved out by the rivers that flow in them. Nor were
there wanting geologists with similar previsions in Germany and
Switzerland.
But none of these early exponents of geological theory came so near to
anticipating the work of the Nineteenth Century as did the illustrious
James Hutton, whose 'Theory of the Earth,' a first sketch of which was
published in 1785, was a splendid exposition of evolution as applied to
the inorganic world. Unfortunately, Hutton's theory was linked to the
extravagancies of what was known at that day as 'Vulcanism' or
'Plutonism,' in contradistinction to the 'Neptunism' of Werner. Hutton,
while rejecting the Wernerian notion of "the aqueous precipitation of
basalt," maintained the equally fanciful idea that the consolidation of
all strata--clays, sandstones, conglomerates, limestones and even
rock-salt--must be ascribed to the action of heat, and that even the
formation of chalk-flints and the silicification of fossil wood were due
to the injection of molten silica!
What was still more unfortunate in Hutton's case was that, in his
enthusiasm, he used expressions which led to his being charged with
heresy and even with being an enemy of religion. His writings were
further so obscure in style as often to lead to misconception as to
their true meaning, while his great work--so far as the fragment which
was published goes--contained few records of original observations on
which his theory was based.
Dr Fitton has pointed out very striking coincidences between the
writings of Generelli and those of Hutton, and has suggested that the
latter may have derived his views from the eloquent Italian friar[10].
But for this suggestion, I think that there is no real foundation.
Darwin and Wallace, as we shall see later, were quite unconscious of
their having been forestalled in the theory of Natural Selection by Dr
Wells and Patrick Matthew; and Hutton, like his successor Lyell, in all
probability arrived, quite independently, and by different lines of
reasoning, at conclusions identical with those of Generelli and
Desmarest.
Although, as we shall see, Hutton failed to greatly influence the
scientific thought of his day, yet all will now agree with Lyell that
'Hutton laboured to give fixed principles to geology, as Newton had
succeeded in doing to astronomy[11]'; and with Zittel that '_Hutton's
Theory of the Earth_ is one of the masterpieces in the history of
geology[12].'