傳統所得分配的文獻，基本上立足於社會福利函數理論，傾向於要求所得分配均等化。由於不同的所得分配可視為不同的社會境界（social state），其他福利經濟理論所提供的工具包括公平性理論在內，應該也可用於建立評價所得分配的標準。本文假定個人或家庭消費的財貨組合是其最適化選擇，定義所得分配的公平性作為評價的依據；文中提出的定理。証明在純交易社會不等值秉賦分配可能導致具公平性的均衡，則足以說明不均等所得分配也可能符合公平性，因此擺脫傳統對分配均化的執著。Baumol（1982）可以說是文獻中唯一應用公平性理論於實證者，本文則進一步引申其超公平性的觀念以評價所得分配，說明偏好差異是不均等分配可能符合公平性的充分條件。

　　　　　The existing literature that primarily bases the evaluation of income distribution on the theory of social welfare function tends to place emphasison the equalization of distribution. Considering different income distributions as different social states, theories in welfare economics, such as thetheory of fairness, may provide other criteria for evaluating distributions.This paper proposes to define fair income distribution in terms of fairnessin the resulting commodity distribution, assuming the individual or household comsumption bundle is chosen optimally. Therefore, the theorem thatproves unequal value endowments can induce fair commodity distributionat the equilibrium suggests the fair income distribution could be unequal,which makes it possible to take departure from the existing literaturesince unequal distribution could be favored by fairness criterion. Baumol'sstudy (1982), the only empirical application of fairness theory until now,provides the heoretical reference for this paper in applying the theory todemonstrate that preference difference can cause the result of fair andunequal income distribution.