Skip to main content

Full text of "Man In The Modern World"

See other formats

DARWIN'S great book, The Origin of »V/wf*:.v, comprised two
quite distinct elements. In the first place, it demonstrated, with
a vast wealth of examples, that the. current theory of (he (ixity
of species was untenable, whether in its theological tfuisc of special
creation or in any other form; it simply would not (it the facts of
nature. The facts of nature demanded an evolutionary theory:
gradual change was the rule in life, constantly producing new types
—not only new species, but also larger groups of every degree, In
the second place, Darwin proposed a mechanism to account for evolu-
tion—the theory of Natural Selection, by which favourable varieties
would automatically be accumulated and the apparent, purposeful-
ness of life could be accounted for in straightforward mechanistic
It was this latter element which gave Darwin's work its influence
among professional biologists, Many of (hem went ripe for conversion
to the idea of evolution, but before iiJf>|) no one had put forward any
but the most improbable suggestions as to how evolution could have
been brought about, T. H. Huxley, for instance, records how, when
he read the Origin, he said to himself, ullow stupid of me not to
have thought of that!" and from then on became the champion of
This Darwinian view of evolution was generally accepted by bio-
logists in the latter part of last century. But about 1890 doubts began
to be thrown upon it, and around 1910 it hud become so unfashion-
able that some critics proclaimed the death of Darwinism. By Dar-
winism, of course, was meant the selectionist theory of the method of
evolution: the fact that evolution has occurred was never seriously
questioned by biologists after 1859, t^t-P*- hy & f<-w survivors from the
prc-Darwinian period, and a very lew later cranks*
This sceptical attitude of the early twentieth century was due to
two main causes. For one thing, orthodox Darwinism was tending
to become purely speculative, invoking natural selection to explain
anything and everything without requiring proof and without pro-
viding any explanation of the, machinery by which the results could
be brought about, For another, genetics had discovered the fact of
mutation—in other words, that hereditary change proceeds by jumps;
and the theory was advanced that evolution proceeded by large jumps,
not by the gradual change which was the keystone of Darwin's* view,