...which we exchange for what is supposed at the time to contain the value of an equal quantity. Labor cannot, it must generally be hurtful. It is the maxim...prudent master of a family, never to attempt to make a labor, that all the wealth of the world was originally purchased; and its value, to those who possess...

...what we acquire with the toil of our own body. Labour was the first price, the original purchase-money that was paid for all things. It was not by gold or by silver, but by labour, that aU the wealth of the world was originally purchased, and its value is precisely equal to the quantity...