All taxes, and an the revenue which is founded upon them, all salaries, pensions, and annuities of every kind, are ultimately derived from some one or other of those three original sources of revenue, and are paid either immediately or mediately from the wages of labour, the profits of stock, or the rent of land.

When those three different sorts of revenue belong to different persons, they are readily distinguished; but when they belong to the same they are sometimes confounded with one another, at least in common language.

A gentleman who farms a part of his own estate, after paying the expense of cultivation, should gain both the rent of the landlord and the profit of the farmer.

He is apt to denominate, however, his whole gain, profit, and thus