inaccessible to the understanding,
can awaken no interest, the fundamentals of the art of teaching were
to go gradually from the known to the unknown, from the easy to the
difficult. It is the preexistent "known" which excites expectation and
_opens the door_ to the novel "unknown"; and it is the already present
"easy work" which opens new ways for penetration, and puts the
attention into a state of expectation.

Thus, according to the conceptions of pedagogy, it should be possible
to "prepare good offices for oneself," the cooperation of the
psychical concomitants of the attention. Everything would depend on
skilful manipulation between the known and the unknown and similar
things: the clever teacher would be like the great military
strategist, who prepares the plan of a battle upon a table; and man
would be able to _direct man_, leading him wheresoever he pleases.

This, moreover, has long been the materialistic principle which
governs psychology. According to Herbert Spencer, the mind is at
first, as it were, an indifferent day, on which external impressions
"rain," leaving traces more or less profound. "Experiences" are,
according to him and the English empiricists, the constructive factors
of the mind even in its highest activities. Man is what experience has
made him; hence, in education, by preparing a suitable structure of
experiences, it is possible to _build up the man_. A conception not
less materialistic than that which presented itself for a moment
before the marvelous progress of organic chemistry, when the series of
syntheses succeeded that of analyses. It was then believed that a
species of albumen might be manufactured synthetically, and as albumen
is the organic basis of the cells, and as the human ovum is nothing
but a cell, man himself might one day be manufactured on the chemist's
table. The conception of man as the creator of man was quickly
discredited in the material domain; but the psychical _homunculus_
still persists among the practical conceptions of pedagogy.

No chemical synthesis could put into the cell, apparently nothing more
than a simple clot of nucleated protoplasm, that _activity sine
matter_, that potential vital force, that mysterious factor which
causes a cell to develop into man.

And the elusive attention of children would seem to tell us that the
psychical man is subject to analogous laws of auto-creation.

The most modern school of spiritualistic psychologists, to which