Trade-offs are an inherent part of life. We all recognize this from our private budgets. To fix the roof, we may have to accept a less extravagant summer vacation. When we pick a cheaper wine, we can splurge on dessert.
Trade-offs also pervade environmental policy: Cutting more of one pollutant, for example, leaves fewer resources to address other issues. For example, coal is phenomenally polluting, but it also provides for cheap and reliable power, which drives development. Over the past 30 years, China has lifted 680 million people out of poverty, mostly through the use of coal. The average Chinese has become more than 13 times richer.