At a personal level, we intuitively know that trading our labor (then
using the money wages as the means of transactions) gives us a higher standard of living than if we tried to produce everything ourselves. As individuals, we know and act on the knowledge that specialization enhances our individual incomes and wealth.
But this knowledge does not seem to hold in our perceptions of the
national economy. We know that a country will be wealthier and have a better life if the country specializes in producing those products that it is good at producing, exporting the surplus, and using the proceeds to buy imports. Yet the notion that the gains from trade should be measured by what we import, not by what we export, is difficult for many.