Rapid and comprehensive social change is required to mitigate pressing environmental issues such as climate change. Social tipping interventions have been proposed as a policy tool for creating this kind of change. Social tipping means that a small minority committed to a target behaviour can create a self-reinforcing dynamic, which establishes the target behaviour as a social norm. The possibility of achieving the large-scale diffusion of pro-environmental norms and related behaviours with an intervention delimited in size and time is tempting. Yet, the canonical model of tipping, the coordination game, may evoke overly optimistic expectations regarding the potential of tipping, due to the underlying assumption of homogenous preferences. Relaxing this assumption, we devise a threshold model of tipping pro-environmental norm diffusion. The model suggests that depending on the distribution of social preferences in a population, and the individual cost of adopting a given pro-environmental behaviour, the same intervention can activate tipping, have little effect, or produce a backlash. Favourable to tip pro-environmental norms are widespread advantageous inequity aversion and low adoption costs. Adverse are widespread self-regarding preferences or disadvantageous inequity aversion, and high costs. We discuss the policy implications of these findings and suggest suitable intervention strategies for different contexts.

Hubris is a tendency of leaders to hold an overly confident view of their own capabilities and to abuse power for their own selfish goals, sometimes with disastrous consequences for organizations. A major reason for hubris is the rigorous selection process leaders typically undergo. This study proposes a governance mechanism used successfully in history to tackle hubris: partly random selections, which combine competitive selections by competence with lotteries. A frequently voiced concern about the use of lotteries is that it takes no account of the competence of the leader chosen. We propose that partly random selections can mitigate the disadvantages of both competitive selections alone and lotteries alone and reduce hubris in leaders. We conduct a test of this governance mechanism by means of a computerized laboratory experiment. Our results show that partly random selections significantly reduce the hubris of group leaders.

The evolutionary legacy hypothesis proposes that an evolved reciprocity-based psychology affects human behavior in anonymous one-shot interactions when reciprocity is not explicitly possible. Empirical support rests on experiments showing that altruism among adults increases in the presence of stylized eye spots or faces. Such stimuli do not affect material payoffs, but they are assumed to activate a person’s reciprocity-based psychology. We identify two versions of the evolutionary legacy hypothesis. The weak hypothesis posits that reputational concerns can generate altruism in the absence of opportunities for a good reputation. The strong hypothesis posits that reputational concerns alone can explain anonymous one-shot altruism, and they can do so specifically in lieu of explanations based on group selection. A number of experimental studies support the weak hypothesis but are merely consistent with the strong hypothesis. To address both the weak and strong hypotheses, we conducted an eye spot experiment with children. Altruism can vary by age or sex in childhood, and under the strong hypothesis this kind of variation should reveal associated variation in sensitivity to eye spots. Although we found significant variation in altruism among children, we found no corresponding variation in sensitivity to eye spots. More generally, we found no eye spot effects of any kind. We discuss the possibility that eye spots might only affect altruism under specific conditions. We further argue that conditional effects do not refute the weak hypothesis in any way, but they do suggest potential limitations on the explanatory scope of the strong hypothesis.