The same view is held by some theoretical writers.

According to Cairnes “slavery, as a permanent system, has need not merely of a fertile soil, but of a practically unlimited extent of it. This arises from the defect of slave labour in point of versatility. As has been already remarked, the difficulty of teaching the slave anything is so great—the result of the compulsory ignorance in which he is kept, combined with want of intelligent interest in his work—that the only chance of rendering his labour profitable is, when he has once learned a lesson, to keep him to that lesson for life. Accordingly where agricultural operations are carried on by slaves, the business of each gang is always restricted to the raising of a single product.… Whatever crop may be best suited to the character of the soil and the nature of slave industry, whether cotton, tobacco, sugar, or rice, that crop is cultivated, and that alone. Rotation of crops is thus precluded by the conditions of the case. The soil is tasked again and again to yield the same product, and the inevitable result follows. After a short series of years its fertility is completely exhausted, the planter—“land-killer” he is called in the picturesque nomenclature of the South—abandons the ground which he has rendered worthless, and passes on to seek in new soils for that fertility under which alone the agencies at his disposal can be profitably employed.… Slave cultivation, wherever it has been tried in the new world, has issued in the same results. Precluding the conditions of rotation of crops or skilful management, it tends inevitably to exhaust the land of a country and [[304]]consequently requires for its permanent success not merely a fertile soil but a practically unlimited extent of it.” Therefore expansion is a necessity of slave societies[16].

In the same sense Weber, speaking of the ancient states of Asia and Europe, remarks that slavery is uneconomical, where a dense population and high prices of the land render an intensive cultivation necessary[17].

It is easy to see that these arguments do not apply to slavery as practised by savages. Rotation of crops and skilful management are wanting among most savage tribes, whether they keep slaves or not. Moreover, as we have already remarked, the slaves kept by them are not pieces of machinery, nor, as in the United States, kept in compulsory ignorance; they are rather regarded as members of the master’s family; there is no great difference between master and slave[18]. We may therefore suppose that, whether a savage tribe keeps slaves or not, agriculture is carried on in the same manner.

Loria also holds that slavery requires an abundant supply of ground; but his arguments are quite different from Cairnes’. His reasoning is as follows.

As long as there is land not yet appropriated, which a man destitute of capital can take into cultivation, capitalistic property cannot exist; for nobody is inclined to work for a capitalist, when he can work for his own profit on land that costs him nothing. If, then, the capitalist wants by any means to get a profit, he must violently suppress the free land to which the labourer owes his force and liberty. And as long as the population is scarce and therefore all land cannot possibly be appropriated, the only means of suppressing the free land is by subjugating the labourer. This subjugation assumes at first the form of slavery; afterwards, when the decreasing fertility of the soil has to be made up for by a greater fertility of labour, slavery gives place to serfdom, which is milder and makes labour more productive.

When the population increases, and all land that can be cultivated [[305]]by labour without the aid of capital had been appropriated, quite another state of things prevails. The labourer has now no other resource but to sell his labour to the capitalist for such wages as the latter likes to give; he is compelled to yield to the capitalist the greater part of the produce of his labour. Now the latter need no longer use violence to get his profit; for it falls to him by the automatic operation of the social system. Yet, even then the capitalistic régime is not absolutely certain to arise, for there is still land not yet appropriated, that can be cultivated with the aid of capital. If, therefore, the labourers could save a portion of their earnings and thus accumulate capital, they would be able to take this land into cultivation and so make themselves independent of their employers. This consideration induces the capitalist to keep wages so low that they cannot exceed the immediate wants of the labourers, which he brings about by various artificial means.

When, finally, a further increase of population makes the total appropriation of the land possible, the mere appropriation of it by the capitalist class renders the labourers for ever subjected. The capitalist need no longer have recourse to artificial methods of reducing wages; the system operates automatically. The capitalists have only to retain the land for themselves; they will then secure a perpetual revenue at the cost of the labouring class.

“The basis of capitalistic property is thus always the same, viz. the suppression of the free land, the exclusion of the labourer from the appropriation of the land. This is brought about by various means, according to the fertility of the land and the extent to which it has already been appropriated. As long as there is free land fit for cultivation by labour without the aid of capital, the only means of suppressing it are slavery and serfdom; afterwards, when the land not yet appropriated can only be cultivated by one who owns capital, it is sufficient systematically to reduce wages to a level that does not enable the labourers to save; when, finally, the population has so far increased as to make the appropriation of all land possible, the capitalists have only to keep the land to themselves”[19]. [[306]]

Many objections can be made to Loria’s arguments. He is constantly confusing capitalist and landlord. He seems to consider capitalists and labourers as two strictly separated classes, though we see continually people passing from one class to the other. And when he tells us that, if wages were higher, the labourers would save a portion of their earnings and so accumulate capital, but that the employers, wishing to prevent this, keep wages low,—he ascribes to both capitalists and labourers so much forethought and consciousness of class-interest as men scarcely ever have, except in books on political economy[20]. Yet we cannot think but that in the main Loria is right. The gist of his reasoning is what we have already remarked in the beginning of this paragraph. As long as there is an abundance of land not yet appropriated, and therefore at the disposal of whoever may choose to cultivate it, nobody applies to another for employment, and the only labourers a man can procure are forced labourers. But when all land has been appropriated, those who own no land are at the mercy of the landholders, and voluntarily serve them; therefore slaves are not wanted.