The Wealth of Nations by Part 3 Chapter 2 Page 18

aside what was judged necessary for keeping up the stock, which was restored to the proprietor when the farmer either quitted, or was turned out of the farm.

Land occupied by such tenants is properly cultivated at the expense of the proprietor as much as that occupied by slaves. There is, however, one very essential difference between them. Such tenants, being freemen, are capable of acquiring property, and having a certain proportion of the produce of the land, they have a plain interest that the whole produce should be as great as possible, in order that their own proportion may be so.

A slave, on the contrary, who can acquire nothing but his maintenance, consults his own ease by making the land produce as little as possible over and above that maintenance. It is probable that it was