power over the air. Nor is it alone of operations mechanical that the
law holds good: it is universal; and its application to pure mental
action may be shown without difficulty. A single act of the mind is
represented by the formation of a simple sentence. The process consists,
first, in the mind's _fixing upon and resting in_ an object, which
thereby becomes the subject of the sentence; and, secondly, in
predication, which is movement, represented by the verb. The reader will
easily supply himself with instances and illustrations of this, and need
not, therefore, be detained.

In the economy of animal and vegetable existence, as in all that Nature
makes, we observe the same inevitable association. Here is perpetual
fixity of form, perpetual flux of constituent,--the ideas of Nature
never changing, the material realization of them never ceasing to
change. A horse is a horse through all the ages; yet the horse of to-day
is changed from the horse of yesterday.

If one of these principles seem to get the start, and to separate
itself, the other quickly follows. No sooner, for example, does any
person perform an initial deed, proceeding purely (let us suppose) from
free will, than Nature in him begins to repose therein, and consequently
inclines to its repetition for the mere reason that it has been once
done. This is Habit, which makes action passive, and is the greatest of
labor-saving inventions. Custom is the habit of society, holding the
same relation to progressive genius. It is the sleeping partner in the
great social firm; it is thought and force laid up and become
fixed capital. Annihilate this,--as in the French Revolution was
attempted,--and society is at once reduced to its bare immediate force,
and must scratch the soil with its fingers.