The Wealth of Nations by Part 1 Chapter 8 Page 12

maintenance of four children, it is supposed, may be nearly equal to that of one man.

The labour of an able-bodied slave, the same author adds, is computed to be worth double his maintenance; and that of the meanest labourer, he thinks, cannot be worth less than that of an ablebodied slave. Thus far at least seems certain, that, in order to bring up a family, the labour of the husband and wife together must, even in the lowest species of common labour, be able to earn something more than what is precisely necessary for their own maintenance; but in what proportion, whether in that above mentioned, or in any other, I shall not take upon me to determine.

There are certain circumstances, however, which sometimes give the labourers an advantage, and enable them to raise their wages