Whether you follow a vegan diet or are a devoted carnivore, carry canvas or plastic, you are one of 7.5 billion people. The ecological effect of your choices is minuscule. And yet they have a big effect on how others see you, and how you see yourself. Psychologists found that prodding people to worry about social status increased their interest in buying green versus nongreen items—but only if they were shopping in public.  People in Washington State and Colorado were willing to pay a premium of $430 to $4,200 (results varied by zip code) for the green-signaling Prius over an equally efficient car that didn’t broadcast its virtue. 
Surveys of tens of thousands of British people suggest that green behaviors such as buying recycled products and taking public transit increased life satisfaction—but only insofar as they made people feel green. And feelings can be misleading: Most people who called themselves green never carpooled or avoided flying. 
Self-congratulation, moreover, can lead to self-indulgence. When people shopped in a green (versus conventional) simulated online store, they felt like they’d done their good deed for the day and were more likely to cheat or steal in a subsequent task—an effect psychologists call “moral licensing.”  Similarly, getting weekly feedback on water consumption reduced people’s water use by 6 percent, but it increased their electricity use by 5.6 percent—as if they felt that being careful in one area entitled them to relax in another. 
Trying to bribe people into green behavior may also backfire, by crowding out motivations like civic duty. When Indian villagers were given material incentives to conserve forest resources, they grew more likely to say that protecting forests is important for economic (versus environmental) reasons—and their behavior grew less conservation-oriented.  Likewise, when Swiss people were asked whether they’d support a nuclear-waste facility in their community (thus putting the need for low-carbon power sources ahead of local safety concerns), half said yes; when several thousand dollars were offered to sweeten the deal, however, three out of four said no. 
Not everyone wants to be seen as a tree-hugger, of course. While some people try to look green, others do the opposite—they adopt Earth-unfriendly behaviors so as to avoid appearing green. People who reject a “pro-environment” identity carried out low-visibility green behaviors more than high-visibility ones. 
Men are more likely than women to hide their greenness—maybe because both sexes associate environmentalism with femininity. In experiments, shoppers who used a canvas versus a plastic bag were rated as more feminine, and men avoided products that were marketed as green—unless their manhood was affirmed first. Given all this, the researchers suggested, environmentalists might want to emulate companies that have successfully marketed stereotypically feminine products to men, such as the diet soda Pepsi Max, Powerful Yogurt, and Broga—yoga classes for bros. 
 Agrawal et al., “Motivational Crowding in Sustainable Development Interventions” (American Political Science Review, Aug. 2015)
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