er extrinsic circumstances. Then, if
they gradually become corrupted and disappear, they must at least be
discoverable in full purity where these disturbing influences have not
yet acted; but it is especially vain to look for them in children and the
ignorant. Perhaps, however, these possess such principles unconsciously;
perhaps they are imprinted on the understanding, without being attended
to? This would be a contradiction in terms. To be in the mind or the
understanding simply means "to be understood" or to be known; no one can
have an idea without being conscious of it. Finally, if the attempt be
made to explain "originally in the mind" in so wide a sense that it would
include all truths which man can ever attain or is capable of discovering
by the right use of reason, this would make not only all mathematical
principles, but all knowledge in general, all sciences, and all arts
innate; there would be no ground even for the exclusion of wisdom and
virtue. Therefore, either all ideas are innate or none are. This is an
important alternative. While Locke decides for the second half of the
proposition, Leibnitz defends the first by a delicate application of the
concept of unconscious representation and of implicit knowledge, which his
predecessor rejects out of hand.

[Footnote 1: According to Fox Bourne this first book was written after the
others. Geil _(Ueber die Abhaengigkeit Lockes von Descartes_, Strassburg,
1887, chap, iii.) has endeavored to prove that, since the arguments
controverted are wanting in Descartes, the attack was not aimed at
Descartes and his school, but at native defenders of innate ideas, as Lord
Herbert of Cherbury and the English Platonists (Cudworth, More, Parker,
Gale). That along with these the Cartesian doctrine was a second and
chief object of attack is shown by Benno Erdmann in his discussion of the
treatises by G. Geil and R. Sommer _(Lockes Verhaeltnis zu Descartes_,
Berlin, 1887) in the _Archiv fuer Geschichte der Philosophie_, ii, pp.
99-121.]

Locke's positive answer to the question concerning the origin of ideas is
given in his second book. Ideas are not present in the understanding from
the beginning, nor are they originated by the understanding, but received
through sensation. The understanding is like a piece of white paper
on which perception inscribes its characters. All knowledge arises in
experience. This is of two kinds, derived either from the external senses
or the intern