Safeguarding the environment ranks high on political and social surveys. Yet a yawning gap exists between good intentions and reality. Although Americans express strong support for reducing air and ground pollution, few give up their cars or recycle their AA batteries instead of throwing them in the trash.

Why are people's words and actions so contradictory? Economists who study such behavior say the only variables that really matter to most individuals are time and money: How much would a gallon of gasoline have to cost before the masses switch to mass transit? How frequently would buses have to run to attract crowds of riders? Fortunately, experts in the young discipline of environmental psychology point out that other influences can strongly affect our choices. Understanding these dynamics, and how to exploit them, may prod citizens to embrace greener ways.

This article was originally published with the title Thinking Green.

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