When "The Origin of Species" appeared fifty years ago Romantic
speculation, Schelling's and Hegel's philosophy, still reigned on the
continent, while in England Positivism, the philosophy of Comte and
Stuart Mill, represented the most important trend of thought. German
speculation had much to say on evolution, it even pretended to be a
philosophy of evolution. But then the word "evolution" was to be taken
in an ideal, not in a real, sense. To speculative thought the forms and
types of nature formed a system of ideas, within which any form could
lead us by continuous transitions to any other. It was a classificatory
system which was regarded as a divine world of thought or images, within
which metamorphoses could go on--a condition comparable with that in
the mind of the poet when one image follows another with imperceptible
changes. Goethe's ideas of evolution, as expressed in his "Metamorphosen
der Pflanzen und der Thiere", belong to this category; it is, therefore,
incorrect to call him a forerunner of Darwin. Schelling and Hegel
held the same idea; Hegel expressly rejected the conception of a real
evolution in time as coarse and materialistic. "Nature," he says, "is
to be considered as a SYSTEM OF STAGES, the one necessarily arising from
the other, and being the nearest truth of that from which it proceeds;
but not in such a way that the one is NATURALLY generated by the other;
on the contrary (their connection lies) in the inner idea which is the
ground of nature. The METAMORPHOSIS can be ascribed only to the notion
as such, because it alone is evolution... It has been a clumsy idea in
the older as well as in the newer philosophy of nature, to regard the
transformation and the transition from one natural form and sphere to
a higher as an outward and actual production." ("Encyclopaedie der
philosophischen Wissenschaften" (4th edition), Berlin, 1845, paragraph
249.)
The only one of the philosophers of Romanticism who believed in a
real, historical evolution, a real production of new species, was Oken.
("Lehrbuch der Naturphilosophie", Jena, 1809.) Danish philosophers, such
as Treschow (1812) and Sibbern (1846), have also broached the idea of
an historical evolution of all living beings from the lowest to the
highest. Schopenhauer's philosophy has a more realistic character than
that of Schelling's and Hegel's, his diametrical opposites, though he
also belongs to the romantic school of thought. His philosophical and
psychological views were greatly influenced by French naturalists and
philosophers, especially by Cabanis and Lamarck. He praises the "ever
memorable Lamarck," because he laid so much stress on the "will to
live." But he repudiates as a "wonderful error" the idea that the
organs of animals should have reached their present perfection through
a development in time, during the course of innumerable generations. It
was, he said, a consequence of the low standard of contemporary French
philosophy, that Lamarck came to the idea of the construction of living
beings in time through succession! ("Ueber den Willen in der Natur" (2nd
edition), Frankfurt a. M., 1854, pages 41-43.)
The positivistic stream of thought was not more in favour of a real
evolution than was the Romantic school. Its aim was to adhere to
positive facts: it looked with suspicion on far-reaching speculation.
Comte laid great stress on the discontinuity found between the different
kingdoms of nature, as well as within each single kingdom. As he
regarded as unscientific every attempt to reduce the number of physical
forces, so he rejected entirely the hypothesis of Lamarck concerning the
evolution of species; the idea of species would in his eyes absolutely
lose its importance if a transition from species to species under the
influence of conditions of life were admitted. His disciples (Littre,
Robin) continued to direct against Darwin the polemics which their
master had employed against Lamarck. Stuart Mill, who, in the theory
of knowledge, represented the empirical or positivistic movement in
philosophy--like his English forerunners from Locke to Hume--founded
his theory of knowledge and morals on the experience of the single
individual. He sympathised with the theory of the original likeness of
all individuals and derived their differences, on which he practically
and theoretically laid much stress, from the influence both of
experience and education, and, generally, of physical and social causes.
He admitted an individual evolution, and, in the human species, an
evolution based on social progress; but no physiological evolution of
species. He was afraid that the hypothesis of heredity would carry us
back to the old theory of "innate" ideas.
Darwin was more empirical than Comte and Mill; experience disclosed to
him a deeper continuity than they could find; closer than before the
nature and fate of the single individual were shown to be interwoven in
the great web binding the life of the species with nature as a whole.
And the continuity which so many idealistic philosophers could find
only in the world of thought, he showed to be present in the world of
reality.