k
of consciousness, is always the most compelling in the matter of sleep.
Not the muscles themselves but the attention, the skill, the mental
effort required to direct those muscles, Dr. Thomson says, constitute
the reason for sleep, a reason which, to those who labor only with their
hands, must seem unutterably sad. He says that while muscle work is the
commonest and the simplest, so it is also the most poorly paid and the
most degrading, and that while brain work is ennobling and the highest
type of labor, it is so difficult of attainment and produced only by
such grievous toil that most of us shirk it, even while reproaching
ourselves at our lack of capacity and purpose. The pathetic burden of
unfulfilled possibilities, he says, is the curse of labor, and only in
sleep does man have temporary oblivion through which, for a time, he
forgets his work and, as it were, uses sleep as an anaesthetic for the
pain of labor, to rise therefrom each morning ready to carry his burdens
for another day.

Lack of sleep, to those whose brains are active, speedily brings nervous
disaster, and the consciousness, from being the active superintendent of
the body, becomes inert, and the body drifts like a boat without a
pilot. Lack of sleep to those whose work is muscular means a numbness in
the nerve cells which guide those muscles, so that they disobey the will
or act unreasonably and without direction. But too much sleep, like
over-indulgence in any anaesthetic, is only shirking that duty and
avoiding that effort to which the higher life calls us, and the sluggard
who sleeps more than the tired nerves need is allowing himself to sink
deeper and deeper into a slough of despond. He forgets his toil in
sleep, but it is only by active, conscious effort when awake that his
work may be lifted to the higher plane where the brain is active, where
work ceases to be mechanical and a burden, and where that greatest
reward of personal satisfaction can be obtained.

CHAPTER XIV

_THEORIES OF DISEASE_

Disease may be defined as an abnormal condition of the human body, and
since there is no one condition of the human body which can be
satisfactorily described as normal, there is, therefore, no exact
definition of disease.

What is disease for one person because of a departure from his normal
health might not be recognized as disease in another person of different
normal vitality. Nor is it possible to assign any particular and special