  These facts give barren countries advantages that compensate for the infertility of their soil. Since they are less likely to be invaded, they are less likely to be sacked and devastated; and they are more likely to be worked well, since "countries are not cultivated in proportion to their fertility, but to their liberty" (SL 18.3). This is why "the best provinces are most frequently depopulated, while the frightful countries of the North continue always inhabited, from their being almost uninhabitable" (SL 18.3).