road, and rail to the great distributing centres. In the
town the machinery of mill and factory keeps busy thousands of
operatives, and turns out manufactured products to compete with the
products of the soil for right of way to the cities of the New World
and the Old. Busiest of all are the throngs that thread the streets of
the great centres, and pour in and out of stores and offices. Men rush
from one person to another, and interview one after another the
business houses with which they maintain connection; women swarm about
the counters of the department stores and find at the same time social
satisfaction and pecuniary reward; children in hundreds pour into the
intellectual hopper of the schoolroom and from there to the
playground. Everybody is busy, and everybody is seeking personal
profit and satisfaction.

5. =Mental Activity.=--There is another kind of activity of which
these economic and social phases are only the outward expression, an
activity of the mind which is busy continually adjusting the needs of
the individual or social organism and the environment to each other.
Some acts are so instinctive or habitual that they do not require
conscious mental effort; others are the result of reasoning as to this
or that course of action. The impulse of the farmer may be to remain
inactive, or the schoolboy may feel like going fishing; the call of
nature stimulates the desire; but reason reaches out and takes control
and directs outward activity into proper channels. On the other hand,
reason fortifies worthy inclinations. The youth feels an inclination
to stretch his muscles or to use his brains, and reason re-enforces
feeling. The physical need of food, clothing, and shelter acts as a
goad to drive a man to work, and reason sanctions his natural
response. This mental activity guides not only individual human
conduct but also that of the group. Instinct impels the man to defend
his family from hardship or his clan from defeat, and reason confirms
the impulse. His sociable disposition urges him to co-operate in
industry, and reason sanctions his inclination. The history of society
reveals an increasing influence of the intellect in thus directing
instinct and feeling. It is a law of social activity that it tends to
become more rational with the increase of education and experience.
But it is never possible to determine the quantitative influence of
the various factors that enter into a decision, or to estimate the