A Walrasian Theory of Money and Barter
研究一个每种商品有两种质量且交易者无法区分非自身消费或生产商品质量的物物交换经济，发现竞争均衡中质量差异最小的商品充当交换媒介，引入法定货币可消除扭曲并提高福利，但高通胀会使交易者回归商品媒介。
We study a barter economy in which each good is produced in two qualities and no trader can distinguish between the qualities of those goods he neither consumes nor produces. We show that in competitive equilibrium there exists a (unique) good—the one for which the discrepancy between qualities is smallest—that serves as the <it>medium of exchange:</it> this good mediates every trade. Equilibrium is inefficient because production of the medium would be lower if it were not for its mediating role. Introducing fiat money enhances welfare by eliminating this distortion. However, high inflation drives traders back to the commodity medium.