laborers is practically made.

_The Law of Final Productivity Applicable to the Labor of
Society._--The law of final productivity applies to every mill, shop,
or mine separately considered. If its capital remains fixed in amount,
units of labor produce less and less as they become more numerous. The
product of any unit at any one time may be measured by taking it away
and seeing how much the output of the establishment is reduced. The
law, however, applies to all the mills, shops, mines, etc., considered
as a social complex of working establishments. As the working society
grows larger without growing richer in the aggregate, the power of
labor to produce goods of all kinds grows less. At any one time this
producing power is measured by taking away from every working
establishment a number of its operatives and ascertaining how much
less is produced after the withdrawal. Such a test on the social scale
is never made consciously. Each employer can test in an approximate
way the effect of reducing his own force, and the effect of gradually
enlarging it, and there are influences at work which result in
enlarging one industry when others are enlarged and in causing the
final productivity of labor to be uniform in all. A shoe manufacturer
can tell, in a general way, how much an extra man or two will be worth
to him. It is possible to ascertain by experience about what number of
shoes that additional labor will, in a year, add to the output of the
shoe factory or the number of tons of steel it will add to the present
annual output of a furnace. When these products vary in the case of
different shops, the men are called to the points where the apparent
additions are largest, and the constant tendency is toward a level of
productive power. The building up of an imaginary force from the
beginning presents, in a clear and emphatic way, the fact that the
specific productivity of labor grows less as, other things remaining
the same, workers become more numerous. We should know on _a priori_
grounds that this must be the fact; but we can verify it by
observation and statistical inquiry. Where men are numerous and land
and tools are scarce, labor is comparatively unproductive; and it is
highly productive where land and tools are plentiful. There is no
doubt that crowding the world full of people, without providing the
world with capital in a proportionate way, would impoverish everybody
whose income depends on labor.

_The Law of