“边际效用”与“边际价值理论”的解释

Marginal utility: The least important use to which a unit of a contemplated supply of identical goods can be put. It is this least importantor marginal use which is weighed or considered when one chooses to increase or decrease his supply by one unit, since this is the use (or value) which is tobe  obtained or renounced.

边际效用：预期一定量的同质商品被投入使用时，最不重要的那个用途。当一个人选择增加或减少他的一单位供给时，正是这个最不重要的或边际用途会被权衡或考虑，因为要获得或放弃的正是这个用途（或价值）。

Marginal theory of value: The theory that the value assignedto any good is the importance attached to its use in removing some felt uneasiness and that the value of any unit of  a supply of identical goods is the value assigned to the least important(or marginal)use for which the contemplated number of available units are expected to be used. This is so because a judgment of value always refers solely to the supply with which aconcrete choice is concerned, for it is only the use of this specific (marginal)supply that one must decide to acquire or forego. Since each additional unit of an identical good will be allocated to a lesser valued use than was previously possible, the value attached to each additional(marginal) unit will be lowerthan that assigned to previously held units. Conversely, with each decrease inthe number of units held, there will be an increase in the value of the least important(marginal) use to which the decreased available supply can be applied.The marginal theory of value is the subjective theory of value which is basic to all the theories of Austrian School of Economics.

边际价值理论：赋予任何商品的价值，是它被用于消除被感知到的某些不适时所具有的重要性。对任何一定数量的同质（identical）商品，其任何单位的价值是赋予最不重要（边际）的那个用途的价值，在该用途上，预计在预期中可得的一定数量单位将会被使用。之所以如此，是因为价值的判断总是，并且唯一地是与具体的选择所涉及的供给有关，因为只有在使用这一特定的（边际）供给时，人们才需要决定获取还是放弃。因为每一新增单位的同质商品都会被分配到相较之前可能的用途而言较为次要的用途中，每一新增（边际）单位的价值将低于赋予之前所持单位的价值。相反，随着所持单位的每一减少，最不重要的（边际）用途的价值将会增加，可用于该用途的可得供给现在减少了。边际价值理论是构成奥派经济学所有理论之基础的主观理论。（英文选自米塞斯《人的行动》英文版附录 Mises Made Easier:A Glossary to Luddwig von Mises’ Human Action，作者为PercyL.Greaves,Jr 朱海就翻译）