nd farther;
the grades and shades of doctrine held by his disciples are now almost
beyond reckoning.

Various Forms of Darwinism.

The great majority of these express what may be called popular Darwinism
["Darwinismus vulgaris"], theoretically worthless, but practically
possessed of great powers of attraction and propagandism. It expresses in
the main a conviction, usually left unexplained, that everything "happens
naturally," that man is really descended from monkeys, and that life has
"evolved from lower stages" of itself, that dualism is wrong, and that
monism is the truth. It is exactly the standpoint of the popular
naturalism we have already described, which here mingles unsuspectingly
and without scruple Lamarckian and other principles with the Darwinian,
which is enthusiastic on the one hand over the "purely mechanical"
interpretation of nature, and on the other drags in directly psychical
motives, unconscious consciousness, impulses, spontaneous
self-differentiation of organisms, which nevertheless adheres to "monism"
and possibly even professes to share Goethe's conception of nature!

Above this stratum we come to that of the real experts, the only one which
concerns us in the least. Here too we find an ever-growing distance
between divergent views, the most manifold differences amounting sometimes
to mutual exclusion. These differences occur even with reference to the
fundamental doctrine generally adhered to, the doctrine of descent. To one
party it is a proved fact, to another a probable, scientific working
hypothesis, to a third a "rescuing plank." One party is always finding
fresh corroborations, another new difficulties. And within the same group
we find the contrasts of believers in monophyletic and believers in
polyphyletic evolution, the mechanists and the half-confessed or
thoroughgoing vitalists, the preformationists and the believers in
epigenesis. Opinions differ even more widely in regard to the _role_ of
the "struggle for existence" in the production of species. On the one hand
we have the Darwinism of Darwin freed from inconsequent additions and
formulated as orthodox "neo-Darwinism"; on the other hand we have
heterodox Lamarckism. The "all-sufficiency" of natural selection is
proclaimed by some, its impotence by others. Indefinite variation is
opposed by orthogenesis, fluctuating variation by saltatory mutation
(Halmatogenesis in "Greek"), passive adaptation by the spontaneous
activi