the beginning. There is
indeed an order and classification of things in nature, but it does not
appear on the surface, and for centuries men remained ignorant of the
underlying harmony. Nature is full of valuable secrets, but they lie
concealed from the careless eye. They are to be detected by prying
deeper into individual facts, by putting a thing here and a thing there
together, by pondering on the relationship of things to each other in
their nature, appearance, and cause. It is a remarkable fact that we
not only increase knowledge best by analyzing, comparing, and
classifying objects, experience, and phenomena--even into old age--but
that the deeper we penetrate into the individual qualities and inner
nature of objects, the more we extend and classify our information, the
simpler all the operations of nature become to our understanding. The
surprising simplicity and unity of nature in her varied phenomena is
one of the mature products of scientific study. The most scientific
thinker, then, is only trying to reduce to a simple explanation the
same puzzle which confronted the infant in its cradle. The problem is
the same and the method similar.

It is plain that the process of classifying objects and phenomena in
nature and in society is the _beginning of scientific knowledge_. A
child begins to learn as soon as it notices the resemblances in things
and arranges them into groups. It will appear later that the mind does
not follow a strictly logical method in gaining its groups, that it
falls into natural errors and misconceptions; but in spite of these
eccentric movements, the general trend is toward classifications and
toward the language symbols that express them. In this power to
associate, classify, and symbolize the products of experience in words
is seen the marked difference between man and the animals. The latter
have little power to compare and generalize, that is, to think. On a
still higher plane, the difference between a careless, loose observer
and a well-trained scientific thinker is largely a difference in
accuracy, in inductive and deductive processes.

The important thing for the teacher to determine is whether this
inductive or concept-building tendency furnishes any _solid ground upon
which to base the work of instruction_. Admitting that it is a natural
process, common to both old and young in acquiring knowledge, perhaps
it can be neglected because it will take care of itself. If i