tive power of
labor in the various subgroups precludes the migration of labor, and a
like equalization precludes a migration of capital.

_Equalization of Productive Powers within the Subgroups._--Not merely
must each unit of labor or of capital be able to create as much wealth
in one subgroup as in another, but within the subgroup--the specific
industry--each unit must be able to create as much under one employer
within the industry as under another. The different _entrepreneurs_
must compete with each other on terms of equality, and no one of them
must be able to wrest from a rival any part of the rival's patronage.
So long as one competitor has an advantage over another in his mode
of creating a product, there is no equilibrium within the subgroup.
The more efficient user of labor and capital is able to draw away
labor and capital from the less efficient one, and the self-seeking
impulse which is at the basis of competition impels him to do it. The
producer who works at the greater advantage is foreordained to
underbid and supplant the one who works under more unfavorable
conditions. That a static state may exist and that the movements of
labor and capital from point to point may be precluded, every
competitor within a subgroup must be able to keep his business intact,
hold his customers, and retain in his employment all the labor and the
capital that he has.

_Equality of Size of Productive Establishments not Necessary._--Size
is, as we shall see, an element of efficiency, and the great
establishment often sells goods for less than it would cost a small
one to make them. The small manufacturer often finds that he would
best become a mere merchant, buying some of the products of the great
mill and selling them to his customers, rather than continue making
similar goods. In the general market an approach to equality of size
is usually necessary in order that competitors may be on even terms.
This does not preclude the survival of many small establishments. The
local retailers have an advantage over great department stores in the
filling of small orders. When one has to buy what costs a dollar it
does not pay to spend a dime in car-fares, and waste a dollar's worth
of time in order to secure the thing for ninety cents. Weariness to
customers is here the element that gives to the small producer his
advantage and enables him to keep that part of the business which
comes in the form of many small orders; but small produ