ts and the
grandparents and the representatives of the successive generations (such
notions as those of "food," "breast"). These concepts are not innate;
because no idea can be innate, for the reason that several peripheral
impressions are necessary for the formation of even a single perception.
They are, however, inherited. Just as the teeth and the beard are not
usually innate in man, but come and grow like those of the parents and
are already implanted, piece for piece, in the new-born child, and are
thus hereditary, so the first ideas of the infant, his first concepts,
which arise unconsciously, without volition and without the possibility
of inhibition, in every individual in the same way, must be called
hereditary. Different as are the teeth from the germs of teeth in the
newly-born, so different are the man's concepts, clear, sharply defined
by words, from the child's ill-defined, obscure concepts, which arise
quite independently of all language (of word, look, or gesture).

In this wise the old doctrine of "innate ideas" becomes clear. Ideas or
thoughts are themselves either representations or combinations of
representations. They thus presuppose perceptions, and can not
accordingly be innate, but may some of them be inherited, those, viz.,
which at first, by virtue of the likeness between the brain of the child
and that of the parent, and of the similarity between the external
circumstances of the beginnings of life in child and parent, always
arise in the same manner.

The principal thing is the innate aptitude to perceive things and to
form ideas, i. e., the innate intellect. By aptitude (Anlage), however,
can be understood nothing else at present than a manner of reacting, a
sort of capability or excitability, impressed upon the central organs of
the nervous system after repeated association of nervous excitations
(through a great many generations in the same way).

The brain comes into the world provided with a great number of
impressions upon it. Some of these are quite obscure, some few are
distinct. Each ancestor has added his own to those previously existing.
Among these impressions, finally, the useless ones must soon be
obliterated by those that are useful. On the other hand, deep
impressions will, like wounds, leave behind scars, which abide longer;
and very frequently used paths of connection between different portions
of the brain and spinal marrow and the organs of sense are easier to
travel ev