f the whole
matter. The more the face and eyes are quiet, and the mind is on the
alert, the more a man will see. Seeing is rather a mental than a bodily
act, though of course the bodily organ is necessary to its
accomplishment. To be a good observer, one must maintain a quiet and
composed demeanor, but be thoroughly wide awake within.

XIII.

ERRORS OF THE CAVE.

Improvement comes by comparison. One of the most profound observations
of Bacon is that in which he remarks upon the dwarfing and distorting
influence of solitariness upon the human faculties. The man who shuts
himself up in his own little circle of thought and action as in a cave,
having no consort with his fellows, evolving all his plans from his own
solitary cogitation, must be more than human if he does not become
one-sided, narrow, selfish, bigoted.

A like result, but not so aggravated, is produced, when a man limits his
range of thought and action to those of his own special calling or
profession; when the merchant mingles only with merchants and knows only
merchandise; when the teacher knows nothing but teaching and books; when
the medical man spends every waking hour and every active exercise of
thought upon his healing art; when any man forgets that, in the very
fact of his being a man at all, he is something greater and nobler than
he can possibly be in being merely a merchant, or teacher, or doctor, or
lawyer, or the possessor of any other one special art or faculty.

It is true, indeed, that in order to attain to eminence in any one
department, a man must bend his main energies to that one thing; and he
must give to it much solitary thought and study. But no department of
action is isolated. No interest is unconnected with other interests. No
truth stands alone, but forms a part in the great system of truth. Study
or action, therefore, which is entirely isolated, must needs be dwarfed
and distorted.

A man must go occasionally out of his own sphere in order fully to
understand those very things with which he is most familiar. A man must
study other languages, if he would hope fully to understand his own. A
man must study more than languages merely if he would become a perfect
linguist. The only way to understand arithmetic thoroughly is to study
algebra. A parent who has only one child, and who gives his entire and
exclusive attention to the study of that child, in order that he may, by
a thorough understanding of its nature and disp