Milton Friedman agreed that markets with monopolistic competition are not efficient, but argued that in countries with free trade, the pressure from foreign competition would make monopolies behave in a competitive manner.
米爾頓·佛利民同意有垄断性竞争的市场是无效的，但指出在有自由贸易的国家中来自外部竞争的压力会使垄断成为竞争方式。