THE PROBLEM OF RENT 99
diminishing rate of return after a certain point is passed, if
not throughout,
That this condition of diminishing returns is a reality may
be demonstrated, either by specific experiment, or, more
generally, by the following consideration. If returns to
labour and capital employed on a fixed land-area were
either in constant or increasing proportion to the labour and
capital, it is clear that the economical method of raising
agricultural produce would be by applying very large
amounts of labour and capital on the most fertile land
available and letting the less fertile land remain uncultivated.
The fact that experience leads practical farmers to limit the
intensiveness of their cultivation, and to utilise their further
resources in extending the area under cultivation, may be
taken to imply that neither constant nor increasing returns
are found in practice. By this is not meant that changes in
methods of cultivation, consequent on changes in demand, or
on extension of knowledge of the science and art of agriculture,
 may not provide opportunity for using some
additional labour and capital, on land already cultivated, in
such a way as to give a return greater in proportion to the
cost than was previously secured. It may also occur that a
choice has to be made between alternative methods of cultivation,
 the one involving a smaller outlay of labour and
capital than the other, The larger outlay may be known to
be likely to yield a return more than proportionately greater
than that securable on the smaller outlay, but the choice
may, nevertheless, fall on the smaller outlay, the less intensive
method of cultivation. Were capital abundantly available,
and a market for the produce able to be secured readily, the
more intensive method might be adopted. Thus, even without
 change in agricultural knowledge, changes in other
conditions affecting the farmer may enable him to reap proportionately
 greater returns by employing a greater amount
of capital and labour on his land. The assertion that, in
general, land yields diminishing returns to increased effort
laid out on it, is quite consistent with such facts.
When a farmer is considering what he can afford to offer
for the hire of land, he must necessarily consider the relation