But the most fruitful examination of the idea of wealth comes about when one focuses on what John Stuart Mill had to say about the matter (it is always fruitful to look to the writings of John Stuart Mill). Mill defines wealth as all things which possess exchangeable value. The objects which represent wealth need not necessarily be things which in themselves be useful or agreeable to the possessor, as long as the possessor thinks his goods are tradeable for such other goods as he thinks will bring him direct pleasure, or use; then, for him, such "useless" possessions are wealth. As any study of the notion will show, certain things can only have wealth to its possessor, such as those things which are gratuitously afforded by nature.17

"Wealth, then, may be defined, as all useful or agreeable things which possess exchangeable value; or in other words, all useful or agreeable things except those which can be obtained, in the quantity desired, without labour or sacrifice.
... To an individual, anything is wealth, which, though useless in itself, enables him to claim from others a part of their stock of things useful or pleasant." (Mill.)18