No wonder people have believed this kind of thing. It has been dinned
into their ears for many years. They have read it with their breakfast
coffee and gazed at it in the street cars and even heard it from their
family physicians, until it has become part and parcel of their
thinking; yet all the time the fundamental idea has been false, and
now, at last, the theory is exploded.

So far as the modern laboratory can discover, the nerves of the most
confirmed neurotic are perfectly healthy. They are not starved, nor
depleted, nor exhausted; the fat-sheath is not wanting, there is no
inflammation, there is nothing lacking in the cell itself, and there
is no accumulation of fatigue products. Paradoxical as it may sound,
there is nothing the matter with a nervous person's nerves. The
faithful messengers have borne the blame for so long that their name
has gotten itself woven into the very language as symbolic of disease.
When we speak of nervous prostration, neurasthenia, neuroses,
nervousness, and "nerves" we mean that body and mind are behaving
badly because of functional disorder. These terms are good enough as
figures of speech, so long as we are not fooled by them; but accepting
them in their literal sense has been a costly procedure.

Thanks to the investigations of physiologist and psychologist, usually
combined in the person of a physician, "nervousness" has been found to
be not an organic disease but a functional one. This is a very
important distinction, for an organic disease implies impairment of
the tissues of the organ, while a functional disorder means only a
disturbance of its action. In a purely nervous disorder there seems to
be no trouble with what the nerves and organs are, but only with what
they do; it is behavior and not tissue that is at fault. Of course, in
real life, things are seldom as clear-cut as they are in books, and