the mere pleasures of association, now develop a truly
economic society, the individual depends on other individuals as well
as on nature for the supply of his wants. Economic independence gives
way to interdependence, because the fortune of each man is largely
dependent, not merely on his own efforts, but on the relations which
he sustains to other men. Simple laws of nature still largely control
his income, but social laws also have a certain control over it.

_Exchanges in their Primitive Stage._--The exchanging of products is,
of course, the process with which the organization begins, and this
process is introduced by easy and natural stages. The man who at first
makes everything for himself develops a particular aptitude for making
some one thing; and, though he may still continue to make most things
for himself, he finds it advantageous to barter off a part of the
supply of the one article for the making of which he is especially
well fitted. He seeks out a neighbor whose special aptitude lies in a
different direction and who has a surplus of some other article. It
may be that one is a successful fisherman and the other is, by
preference, a maker of clothing, and that they can get a mutual
benefit by an exchange of food for raiment.[2]

[2] If we were giving a history of the division of labor, we
should have to record the effects of differences of climate
and of agricultural and mineral resources in occasioning, at
an early period, a territorial division of labor. We are here
describing the division of labor which occurs within a
society and in consequence of what may be called social
economic causes.

_The Intermediate Type of Exchanges and the Final One._--In the next
stage a man becomes wholly a specialist, making one kind of product
only and bartering it away for others. It might seem, at the first
glance, that differentiation has now done its full work; but it is
very far from having done so. Making one complete good for consumption
is still a complex operation, which can advantageously be subdivided
in such a way that one man produces a raw material while another works
it up into a useful shape. A gain may be made by a further division of
the manufacturing process, whereby the first worker makes only the
rawest material, another fashions it somewhat, a third carries the
process farther, and a fourth or a still later one completes it. In
modern industry the material must often