f
nothing." Darwin thoroughly understands that he is engaged with the
causes which have produced changes in individuals and in the second
place he is engaged with the mode in which such individual
differentiations tend to mark off a race, a genus, or a species.
Darwin moreover was less occupied in discovering these causes, which
up to the present are either entirely unknown or on which there is
only general information, than in discovering a rational form in which
to establish their reality, to embrace their permanent significance.
But Darwin ascribed too wide a reach to his discovery in this that he
made it an exclusive means of variation in species and neglected the
causes of individual differentiations from the general form. This
mistake however is common to most people who make a step forwards.
Next, if Darwin produces his changes in individual types out of
nothing and thereby excludes the wisdom of the breeder, the breeder on
his part must not only display his wisdom but he must produce out of
nothing real changes in plant and animal forms. But who has given the
impetus to the investigation as to whence these variations and
differentiations proceed? It is again no one but Darwin.

Lately the conception of natural selection has been broadened, by
Haeckel, in particular, and the variation of species has been shown to
be the result of actual change owing to adaptation and inheritance,
whereby adaptation is considered as the source of variations and
heredity as the conserving element in the process. Even this is not
correct in Herr Duehring's eyes. "Peculiar adaptation to the
circumstances of life as they are offered or withheld by nature
supposes impulses and facts which answer to the conception. Hence
adaptation is only apparent and actual causality does not elevate
itself above the lowest steps of physical, chemical and plant
physiology." It is again the name which provokes Herr Duehring. But
how does he deal with the matter? The question is if such changes do
take place in the species of organic beings or not. And again Herr
Duehring has no reply.

"If a plant in the course of its growth takes a direction by which it
gets the most light the result is nothing but a combination of
physical forces and chemical agents, and if we are to call it an
adaptation, not metaphorically but strictly, confusion is certain to
arise in the motion." This man is so exacting with other people
because he is quite well acquainted wit