Principles of Political Economy: Abridged with Critical, Bibliographical, and Explanatory Notes, and a Sketch of the History of Political Economy
John Stuart Mill · en
In [the United States,] England, and Holland, then, for a long time past,
and now in most other countries in Europe, the second requisite of
increased production, increase of capital, shows no tendency to become
deficient. So far as that element is concerned, production is susceptible
of an increase without any assignable bounds. The limitation to
production, not consisting in any necessary limit to the increase of the
other two elements, labor and capital, must turn upon the properties of
the only element which is inherently, and in itself, limited in quantity.
It must depend on the properties of land.
Chapter IX. Of The Law Of The Increase Of Production From Land.
§ 1. The Law of Production from the Soil, a Law of Diminishing Return in
Proportion to the Increased Application of Labor and Capital.
Land differs from the other elements of production, labor, and capital, in
not being susceptible of indefinite increase. Its extent is limited, and
the extent of the more productive kinds of it more limited still. It is
also evident that the quantity of produce capable of being raised on any
given piece of land is not indefinite. This limited quantity of land and
limited productiveness of it are the real limits to the increase of
production.
The limitation to production from the properties of the soil is not like
the obstacle opposed by a wall, which stands immovable in one particular
spot, and offers no hindrance to motion short of stopping it entirely. We
may rather compare it to a highly elastic and extensible band, which is
hardly ever so violently stretched that it could not possibly be stretched
any more, yet the pressure of which is felt long before the final limit is
reached, and felt more severely the nearer that limit is approached.
After a certain, and not very advanced, stage in the progress of
agriculture—as soon, in fact, as mankind have applied themselves to
cultivation with any energy, and have brought to it any tolerable
tools—from that time it is the law of production from the land, that in
any given state of agricultural skill and knowledge, by increasing the
labor, the produce is not increased in an equal degree; doubling the labor
does not double the produce; or, to express the same thing in other words,
every increase of produce is obtained by a more than proportional increase
in the application of labor to the land. This general law of agricultural
industry is the most important proposition in political economy. Were the
law different, nearly all the phenomena of the production and distribution
of wealth would be other than they are.