13-8 Marginal utility—as the quantity of the supply (stock) of a good increases, the utility (value) of each additional unit decreases

Scarcity per se does not equal value, since anything can be substituted by any other things (e.g., see Voskuil’s Scarcity Fallacy and Substitution Principle, respectively).

“The least important end fulfilled by the stock is known as the satisfaction provided by the marginal unit, or the utility of the marginal unit—in short: the marginal satisfaction, or marginal utility.”

“The law of marginal utility depends on no physiological or psychological assumptions but is based on the praxeological truth that the first unit of a good will be used to satisfy the most urgent want, the second unit the next most urgent want, etc.”

Next:

• 13-8a The supply is seller’s demand

Related:

• 11-3.4 ‘Utility’ (marginal, diminishing, increasing) - Specialization beats the Invisible Hand
• 13-4d3 Values cannot be measured
• 11-3.5 There is no universal utility. Utility doesn’t exist in the abstract, it must be rooted in the context and corresponding explanations.