“Every man is rich or poor according to the degree in which he can afford to enjoy the necessaries, conveniences, and amusements of human life. But after the division of labour has once thoroughly taken place, it is but a very small part of those with which a man’s own labour can supply him. The far greater part of them he must derive from the labour of other people, and he must be rich or poor according to the quantity of that labour which he can command, or which he can afford to purchase. The value of any commodity, therefore, to the person who possesses it, and who means not to use or consume it himself, but to exchange it for other commodities, is equal to the quantity of labour which it enables him _to purchase or command_. Labour, therefore, is the real measure of the exchangeable value of all commodities.”[37] This passage permits of but one interpretation. If I am rich, in the sense of owning things with a money price or exchange value, in proportion to the quantity of labor which, by means of these things, I can purchase or command, _quantity of labor_ here can mean but one thing, namely, quantity of _productive power_ as opposed to quantity of toil, pain, subjective sacrifice, or disutility. In society, I am supplied with this world’s goods virtually in proportion to the amount of productive power of labor at my call; and this amount is asserted to be the true measure of value. This we may describe as a view of _labor as potential commodity_. Labor to be performed is commodity in the making. What kind of commodity it shall be in the particular case depends upon the will of him who has command over the labor. A later sentence bears out this explanation perfectly: “[A person’s] fortune is greater or less precisely in proportion to the extent of this power [over labor]; or to the quantity either of other men’s labour, or, what is the same thing, of the produce of other men’s labour, which it enables him to purchase or command. The exchangeable value of everything must always be precisely equal to the extent of this power which it conveys to its owner.”[38] This signifies, then, that the value of any article to its possessor must be measured by the amount of labor which it can command in exchange, _because_ this labor is the means of obtaining valuable articles in general. To Smith, labor is the great homogeneous, undifferentiated, common denominator to the wonderfully diverse mass of goods which come into existence out of it, and the value or “real worth”[39] of each of these goods follows the quantity of the source-stuff turned to its production.