carefully interpreted; and it is not necessary that every individual labourer and employer, and every particular portion of capital, should exhibit the capacity to move from the less to the more advantageous occupation. It is only necessary that a sufficient number of labourers, which may be found in the rising generations successively entering on industrial and business life, and an adequate amount of capital, which may be discovered in fresh accumulations or floating funds, should move or be expected to move; and these quantities may vary at different times and in different employments. But it is not difficult to find cases where the influences of such an amount of mobility as this are inoperative, because the necessary conditions do not exist; and here the assumption of competition implied in the theory of rent does not seem to be realised in a way that the theory contemplates.
It has, for example, been contended that in Ireland there has, broadly speaking, been no alternative occupation to agriculture for a large part of the population. There have been only such other industries as were to be found in a few exceptional districts, and therefore the cultivator of land could not compare his earnings with those to be gained in other employments. So far as this was the case, the assumption of competition implied in the theory of rent did not appear to have been fulfilled. There might be competition; but its only limit would be the necessities of subsistence, and it would not be restrained, as the theory is generally understood to assume, by the alternative of leaving farming and passing into some other occupation. In the case, indeed, of such small cultivators, the comparison would seem generally to lie between the wages to be obtained in other occupations and the earnings of farming, rather than between those earnings and profits; and this consideration may be of more than theoretical importance. But even this lower limit of wages may be conceived as ineffectual, if other occupations are insignificant in extent, or are practically non-existent. Rent is sometimes described as the 'leavings' of profits and wages, but in such cases it may rather be what is left when the necessities of a bare subsistence have been met. The cultivator, having no alternative occupation, may conceivably be forced by competition to offer such a rent as will only permit him to live, and he may offer it with a full knowledge of the conditions of his present position and of the future consequences of his act.
But again, even where the possibility of passing from one place or trade to another may not be beyond the limits of conceivable attainment, it may, from the ignorance or incapacity of the
