jocular and perhaps ridiculous digression, which I desire men to look upon rather as a Dream or Resvery than a rational proposition," he calculates in the Political Arithmetick that, if the people of Ireland and the Highlands of Scotland were all transplanted to England, the resultant rise in rents and in year's purchase would so enrich that kingdom that it could afford to buy the lands and fixtures of its neighbors and to pay the expense of importing their persons and movables. The same idea he elaborated in great detail in the Treatise of Ireland, and he seriously attempted to secure for it the approbation of James II. As a practical proposal, it is preposterous; and the king of course refused to entertain it. But we must consider the circumstances. In the first place, Petty was familiar from his Irish experiences with the idea of deporting a whole population. He doubtless argued that, if a usurper for a mere political reason might transplant all the Irish beyond the Shannon, surely a true king might remove them to England, where, after all, they would be better off than in Connaught, while at the same time they would make his the richest kingdom in Europe. The seventeenth century was less careful of the individual's rights than the nineteenth. In the second place the economics of Petty's proposal are altogether sound. People are wealth. They are, indeed, the chief component of the national capital. The people of Ireland are capital badly situated. Their efficiency will be increased by transplanting them, just as the efficiency of a factory might be by removing it to a better site. The idea is inconsiderate; but, granting Petty's premises, it is by no means absurd.
Petty's theory of value, like his theory of rent, is developed incidentally to the discussion of taxation. It is an uncompromising quantity-of-labor theory. "Let a hundred men work ten years upon Corn, and the same num-
