r or of paper which they happen to
contain. But the wealth which those boots represent is not an
objective fact. It depends upon the opinion which men and women
entertain as to their utility; and these opinions take us into the
subjective regions of human psychology. Let us suppose, for instance,
that we calculated, on the basis of present prices, that the boots in
existence at the present time represented 1/1000 part of our total
wealth. Suppose, then, that a miracle were to happen; that the skies
opened and rained boots upon us, of every size and shape and pattern,
until we had 1000 times as many boots as we had before. Could we say
that our total real wealth had been doubled? Clearly we could not. To
obtain boots for nothing, and to wear a new pair every week, would
make us somewhat better off, but not twice as well off as we were
previously. In other words, the real wealth of a thousand times as
many boots as we have now, is not a thousand times as great as the
wealth of the present number of boots. We are, indeed, practically
restating the Law of Diminishing Utility; and this perhaps is enough
to show that wealth is fundamentally the same thing as utility.

Another point, however, is worth noting. Our real wealth would be
somewhat increased in the case supposed; but if we were to turn to the
money measure of wealth, the opposite result would be far more likely,
For the price of boots would most likely fall to nothing, and the
total value of boots, in the commercial sense, would accordingly be
nothing also. This shows that money values may be a most imperfect
measure of aggregate wealth; for what money values represent is the
product of the quantity of the commodity and its _marginal_ utility,
while aggregate wealth is _total_ utility, which is a very different
thing. This, it may be observed, makes all attempts to compare the
wealth of different countries or different times, and no less to
construct Index Numbers of Prices, imperfect of necessity, and
arbitrary in their foundations.

Sec.4. _Criteria of Policy_. The point has now been reached at which we
must take into account the very important fact which was mentioned at
the close of Chapter III. The maximum utility which the laws of
supply and demand tend to bring about is a maximum _total_ utility
indeed, but one still measured in terms of money. An unequal
distribution of wealth destroys any necessary correspondence between
that and the maximum _real_ util