ost of labor
at its maximum, and it is this which acts as a measure of effective
utility and value.

[2] If we should try to describe all the possibilities in the
case, we should take account of the fact that a man may get a
positive pleasure from his first hour or two of labor and
construct a figure thus to express this fact:--

[Illustration]

_AC_ is the curve representing the sacrifice entailed by
successive hours of labor.

[Illustration]

In like manner we should have to recognize the fact that the
utility of some kinds of goods may not reach a maximum with
the first increment, and should construct a utility curve to
express this fact. _BC_ here represents the increase and the
following decrease in the specific utility of the supply of
an article of this kind.

_The Coincident Measure of Cost and Utility._--It now appears that the
line _CD_ signifies two different things. It measures the utility of
the last unit of the man's consumers' wealth, and it also measures the
sacrifice that he has incurred in order to get it. These are opposing
influences, but are equally strong. The one, of itself, makes man
better off, while the other, of itself alone, makes him worse off. At
the last instant of the working day they neutralize each other, though
in all the earlier periods the utility secured is greater than the
sacrifice incurred and the net gain thus secured has kept the man
working.

_The Point at which Utility and Disutility are mutually
Neutralizing._--At a certain test point, then, production acts on man
in such a way as exactly to offset the effect experienced from the
consuming of the product. Man, as a consumer, has to measure a
beneficial effect on himself, and, as a producer, he has to measure an
unpleasant effect. He finds how much he is benefited by the last unit
of wealth which he gets for personal use, and also how much he is
burdened by the last bit of labor that he performs. If this sacrifice
just offsets the benefit derived from the final consumption, it is the
best unit for measuring all kinds of utilities. A man secures by means
of this final and most costly labor a variety of things, for if he
works up to this point every day in the year, he will have at his
disposal, say, a hundred hours of labor in excess of what he would
have had if he had worked a third of an hour less each day. The
product of this extra labor will be taken in the