The use of a single medium is highly advantageous for the same reasons that a money economy is superior to a barter economy: it makes exchanges possible on an incalculably wider scale.

• 这种对单一交换媒介的使用，就象货币社会之所以比物物交换的原始社会更为进步的原因一样，是相当有利的：因为这使交换可以在不可胜数的大规模情况下得以进行。