Going beyond efficiency: including altruistic motives in behavioral models for sustainability transitions to address sufficiency.

Sustainability transitions require altered individual behaviors. Policies aimed at changing people’s consumption behavior are designed according to efficiency, consistency, and sufficiency principles. Taking into account shortcomings of the first two principles, this paper specifically addresses the sufficiency principle. Sufficiency policies are not very popular due to the fear that they may impede quality of life. This fear might be eased when highlighting the motiva-tional side of sustainable behavior, such as the wish to care for future generations and the world’s poor. This article uses the capability approach (CA), developed primarily by Nobel-laureate economist Amartya Sen (1987a) and philosopher Martha Nussbaum (1993, 2000), to a) include the differentiation between self- and other-oriented goals and behavior, b) build on its demonstrated success in assessing quality of life, and c) assess the sustainability of behavior and policies. These three facets make CA suitable to analyze the effectiveness of sufficiency policies on sustainability and quality of life. To better understand the motivational side of sustainable behavior, CA is here for the first time en-riched through approaches from environmental psychology. This enables us to highlight the idea of intrinsic empow-erment as a building block for sufficiency policies. We close the article by highlighting further avenues for research.