d adornments and a little more for food. Some recreations
may be sacrificed for an occasional book or magazine. One may build a
house or purchase a motor-car instead of going abroad. And whichever
choice is made, related expenditures must be made in consequence for
which, on the assumption of a definite amount of income, compensation
must be made by curtailment of outlay at other points. What seems clear
in general is that one's total budget is relative to the general plan
and manner of life one deems for him the best possible and that this
plan, more or less definitely formulated, more or less steadily
operative, is what really determines how far expenditure shall go in
this direction and in that. The budget as a whole will define for the
individual an equilibrium among his various recognized wants; if the
work of calculating it has been carefully done there will be for the
time being no tendency to change in any item.

If, then, we choose to say in such a case that the individual carries
his expenditure along each line to the precise point at which the last
or marginal utility enjoyed is precisely equal to the marginal utility
on every other line, it seems not difficult to grasp what such a
statement means. Quite harmlessly, all that it can mean is that the
individual has planned precisely what he has planned and is not sorry
for it, and for the time being does not think he can improve upon it. As
there is one earth drawing toward its center each billiard ball of the
dozen in equilibrium in a bowl, so there is behind the budget of the
individual one complex personal conception of a way of life that fixes
more or less certainly and clearly the kinds and intensities of his
wants and assigns to each its share of purchasing power. That the units
or elements in equilibrium hold their positions with reference to each
other for reasons capable of separate statement for each unit seems a
supposition no less impossible in the one case than in the other. To
think of each kind of want in the individual's nature as holding
separately in fee simple and clamoring for full and separate
"satisfaction" in its separate kind, is the characteristic illusion of a
purely formal type of analysis. The permanence of a budget and its
carrying out no doubt require the due and precise realization of each
plotted marginal utility--to go further than this along any one line
would inevitably mean getting not so far along certain others, and thus
a