Earnest, well-meaning environmental messages are supposed to be ineffective relics of a bygone age, when bumper stickers still worked and treehuggers hadn’t realized that self-interest speaks louder than Mother Earth ever could.
But don’t put that Save the Whales t-shirt on eBay just yet. In experiments published August 12 in Nature Climate Change, psychologists found that telling people about carpooling’s money-saving benefits seemingly makes them less likely to recycle.
In short, appeals to self-interest backfired, accidentally encouraging people to behave selfishly in other areas.
“These results reveal the potential for self-interested concerns to inhibit pro-environmental behavior,” wrote the researchers, who were led by Laurel Evans and Greg Maio of the United Kingdom’s Cardiff University.
In the study, 80 Cardiff University undergraduate students were each asked to read statements on a computer about carpooling. Some learned that it saved money, others that it’s good for the environment. A control group learned neither.