beyond static formulae, but, as Professor
Osborn points out (op. cit. page 87.), "it is a very striking fact, that
the basis of our modern methods of studying the Evolution problem was
established not by the early naturalists nor by the speculative writers,
but by the Philosophers." He refers to Bacon, Descartes, Leibnitz, Hume,
Kant, Lessing, Herder, and Schelling. "They alone were upon the main
track of modern thought. It is evident that they were groping in the
dark for a working theory of the Evolution of life, and it is remarkable
that they clearly perceived from the outset that the point to which
observation should be directed was not the past but the present
mutability of species, and further, that this mutability was simply the
variation of individuals on an extended scale."

Bacon seems to have been one of the first to think definitely about the
mutability of species, and he was far ahead of his age in his suggestion
of what we now call a Station of Experimental Evolution. Leibnitz
discusses in so many words how the species of animals may be changed
and how intermediate species may once have linked those that now seem
discontinuous. "All natural orders of beings present but a single
chain"... "All advances by degrees in Nature, and nothing by leaps."
Similar evolutionist statements are to be found in the works of the
other "philosophers," to whom Prof. Osborn refers, who were, indeed,
more scientific than the naturalists of their day. It must be borne in
mind that the general idea of organic evolution--that the present is
the child of the past--is in great part just the idea of human history
projected upon the natural world, differentiated by the qualification
that the continuous "Becoming" has been wrought out by forces inherent
in the organisms themselves and in their environment.

A reference to Kant (See Brock, "Die Stellung Kant's zur
Deszendenztheorie," "Biol. Centralbl." VIII. 1889, pages 641-648. Fritz
Schultze, "Kant und Darwin", Jena, 1875.) should come in historical
order after Buffon, with whose writings he was acquainted, but he seems,
along with Herder and Schelling, to be best regarded as the culmination
of the evolutionist philosophers--of those at least who interested
themselves in scientific problems. In a famous passage he speaks of
"the agreement of so many kinds of animals in a certain common plan of
structure"... an "analogy of forms" which "strengthens the supposition
that they have an a