Sec. 1. We have next to examine the causes of formation of
relatively separate groups of wage earners.
Sec. 2. What is meant by a "relatively separate group"?
Sec. 3. The causes of the existence of these groups in the
United States to-day. Inequality of natural ability;
inequality of opportunity; artificial barriers. All these
contradictory to assumptions behind theory of general rate
of wages.
Sec. 4. Trade unions another factor in the formation of
relatively separate groups. Indirect effects in opposite
direction.
Sec. 5. Each of these groups has a relatively independent
economic career. There are a series of wage levels, all of
which are governed to a considerable extent by the same
forces.
Sec. 6. The way in which the relative plenty or scarcity of
each kind or group of labor affects its wages. Other forces
play a part also.
Sec. 7. The nature of wage "differentials."