other hand, the present value of a field of grain or the young
orchard is dependent upon its utility in meeting a future want. Everything
which enhances prospective utility of any article enhances its value; and
everything which diminishes the chance of such utility, like bad weather,
insects or plant diseases, diminishes the present value. In this way risk
diminishes the value of wealth subject to it and increases the value of
wealth which has passed by it.

In general, the usefulness of anything is no criterion for measuring
value, because other elements of value are more important. Henry C. Carey
says, "Utility is the measure of man's power over nature; value is the
measure of nature's power over man." This may be a striking way of saying
that great utility implies a discovery of uses, while great value often
indicates only difficulty in securing what has great usefulness.

_Exertion as related to value._--Since utility, however essential to value,
is not its measure, we are led to consider whether the exertion required
to obtain any article desired may not measure its worth. This is certainly
a matter of prime consideration, and many have been led to suppose the
cost of production, by which is meant all the exertion necessary to bring
any commodity to its final consumer, to be the sole and absolute measure
of value.

This supposition, if ever correct, is subject to great modifications. None
know better than farmers that a bushel of wheat from one field may have
cost twice as much as a bushel from another field, without any possible
distinction in value. Every mechanic knows that what he has accomplished
with great exertion may have been duplicated by some labor-saving device
with half the exertion, the two values being essentially equal. Nothing is
more common than to find articles in the market sold without regard to
cost because they are superseded by more desirable articles. Indeed, the
most ardent defender of cost as the sole basis of value is obliged to
notice multitudes of exceptions to the rule. Yet it must be granted that
only those articles involving effort in securing them have value at all,
and in general the amount of effort actually put forth has some relation
to our estimate of value.

In general, men do not exert themselves more than necessary to meet wants,
and in any exchange with others estimate the value of what they have
produced by the exertion expended. Yet, as products of the same kind
exch