Self-interest and pro-environmental behaviour

Inspired by the principles used to market physical products, campaigns to promote pro-environmental behaviour have increasingly emphasized self-interested (for example, economic) reasons for engaging with a self-transcendent cause (that is, protecting the environment)(1,2). Yet, psychological evidence about values and behaviour suggests that giving self-interested reasons, rather than self-transcending reasons, to carry out a self-transcending action should be ineffective at increasing self-transcending behaviour more generally(3,4). In other words, such a campaign may fail to cause spillover, or an increase in other, different environmental behaviours(5). Here we show that recycling rates are dependent on the information participants receive about a separate environmental behaviour, car-sharing (carpooling in the USA). In two experiments, we found that recycling was significantly higher than control when participants received environmental information about car-sharing, but was no different from control when they received financial information or (in experiment 2) received both financial and environmental information. Our results suggest that, congruent with value theory, positive spillover from one environmental message to another behaviour (car-sharing to recycling) may occur primarily when self-transcending reasons alone are made salient.