This article explores the ‘rationality wars’, contemporary debates about the nature and scope of rationality across economics, psychology, behavioral public policy and philosophy. It traces the evolution of the concept from classical thinkers and shows how modern disagreements – such as Daniel Kahneman’s logical model versus Gerd Gigerenzer’s ecological approach – restate long-standing philosophical tensions. These divergences arise from the distinct epistemological demands of each discipline. Using Gustavo Bueno’s distinction between concepts (discipline-specific) and ideas (transdisciplinary), the article critiques reductionist attempts to impose one framework as definitive. Instead, it argues for a pluralistic, scientifically grounded understanding of rationality that respects diverse aims, methods and standards.

Despite a long history of research on democratic backsliding, the process itself − in which the executive branch amasses power and undermines democratic processes and institutions − remains poorly understood. We seek to shed light on the underlying mechanisms by studying democratic near misses: cases in which a period of autocratic governance is quickly reversed or full backsliding is prevented at the last minute. Building on the literature on near misses in sociotechnical systems such as nuclear power plants, we adapt the drift-to-danger model to the study of democratic systems. Two key findings emerge: First, democratic backsliding is often triggered by political elites pushing the boundaries of their power by violating norms, which are crucial yet vulnerable safeguards for democracy. Second, democratic backsliding is unpredictable and non-linear, being driven by the interaction between political elites and the public. Norm-violating elites may feel legitimized by a supportive public that sees norm violations as justified. At the same time, political elites may signal that norm-violating behaviour is acceptable, potentially leading the public to adopt anti-democratic beliefs and behaviours. We identify risk factors that make norm violations more likely and outline behavioural sciences-based interventions to address these violations.

Safety villages are interventions that aim to boost children's knowledge and behaviour regarding risk-taking behaviours and their consequences via an experiential learning approach. In safety villages, children experience scenarios involving risks that resemble real-life situations. We investigated the extent to which desirable learning outcomes from a single-session safety village visit are visible outside the safety village context. In a well-powered quasi-experimental preregistered field study, we compared students (aged 11–13) who received experiential safety education to a control group of students who had not yet received the education on three important learning outcomes: Knowledge-application, risk-taking behaviour and general risk-taking tendencies. Data were collected outside of the safety village environment, before or after the visit, and without explicit reminders of the visit. Results show students who received experiential safety education outperformed those who did not yet receive experiential education on knowledge-application and reduced risk-taking behaviours. We found no differences on general risk-taking tendencies. These results show a single visit to a safety village visit can reduce risk-taking of risks that were experienced in the village, but not general risk-taking tendencies. Theoretical and policy implications are discussed.

Pro-environmental behavior, including waste sorting and recycling, involves a combination of future-oriented (futureness) and other-oriented (otherness) attributes. Inspired by the perspective of intergenerational choice, this work explores whether eliciting concerns for future others could increase public support for recycling policy and recycling behavior. Study 1 consisted of an online random controlled trial and a laboratory experiment. In Study 1A (N = 400), future other-concern was primed using a static text manipulation, whereas in Study 1B (N = 192), a dynamic virtual manipulation was employed. The results showed that people in the conditions that elicited future other-concern reported greater household recycling intentions and more actual recycling behavior than those in the control conditions. Study 2A (N = 467) and Study 2B (N = 600) generalized this effect on the acceptance of the ‘Certain Time Certain Place’ waste sorting policy in China. Consistent with the intergenerational choice model, envisioning the future of subsequent generations is more impactful in gaining policy approval than merely envisioning a future time. These findings provide a new method for promoting public policy approval and recycling behavior, suggesting that people could become environmentally friendly when they are guided to consider future others.

Dark patterns that manipulate consumer behaviour are now a pervasive feature of digital markets. Depending on the choice architecture utilised, they can affect the perception, behaviour and purchasing patterns of online consumers. Using a novel empirical design, we find strong evidence that individuals across all groups are susceptible to dark patterns, and only weak evidence that user susceptibility is materially affected by commonly used general proxies for consumer vulnerability (such as income, educational attainment or age). Our conclusions provide empirical support for broad restrictions on the use of dark patterns, such as those contained in the EU’s Digital Services Act, that protect all consumer groups. Our study also finds that added friction, in the form of required payment action following successful deployment of dark patterns, reduces their effectiveness. This insight highlights the instances in which dark patterns would be most effective – when no further action is required by the user. Consumer vulnerability is therefore more pronounced when dealing with online providers who store users’ payment details and can rely on a ‘single click’ to complete the purchase.

Nudging is often proposed as a promising policy approach for improving healthy choices among lower socioeconomic position (SEP) populations. However, nudges may not suit lower SEP contexts and empirical studies are scarce. We examined the efficacy of a repositioning nudge at a supermarket in a deprived neighborhood in improving healthier snack purchases and described customers’ healthy grocery shopping needs. Daily sales were collected during 4-week control and intervention periods, where healthier snacks replaced unhealthy snacks at the checkout. Besides, questionnaires were administered. More healthier snacks were sold per day during the intervention (Median = 2.50, Q1 = 2.00, Q3 = 3.50) than control period (Median = 0, Q1 = 0, Q3 = 1.00), B = 1.77, z = 5.50, p < .001, incidence rate ratio = 5.87 (95%CI [3.52, 10.17]). Despite statistical significance, the absolute number of healthier snacks sold remains negligible. Customers report to find it important to eat healthily and to think carefully about their groceries, but to hardly buy snacks at the checkout and desire a healthy and affordable food offer. Repositioning nudges may not suit the circumstances and needs of lower SEP populations. Interventions must be tailored to lower SEP groups and integrated with system-level policies.

Littering involves throwing away waste in places not designated for it, harming the environment. This study introduces a strategy to encourage more use of Littergram, an app designed to fight littering. Littergram allows users to photograph litter and share these images publicly, alerting local councils to clean up the waste. The study aimed to increase user engagement with Littergram by implementing an intervention designed using the Behaviour Change Wheel (BCW), a comprehensive framework for developing behaviour change interventions. We developed and applied a digital campaign through emails, following BCW guidelines. The process began with identifying the behaviour we wanted to change. We conducted a survey to understand what influences this behaviour and selected techniques for changing behaviour based on these insights. The campaign involved sending targeted emails to Littergram users. There was an increase in the use of Littergram during the campaign, and growth returned to initial levels after the campaign ended. This outcome shows that the approach can effectively increase engagement temporarily. Future research should focus on challenges in maintaining long-term behaviour change.

Possibly the most important argument for the permissibility of choice architecture is the inevitability argument (IA), which states that if choice contexts are to inevitably influence individuals in some way, they should be arranged to best promote their welfare. Opponents point out a moral difference between influence from unmodified environments (including environments designed without any thought given to behavioral influence) and environments modified specifically to produce behavioral effects. Only the latter are said to subvert the will of those affected, and thereby raise concerns pertaining to manipulation, mistreatment of rational agency, etc. We argue, however, that if choice architects can reliably predict the behavioral effects of both the unmodified environment and available alternatives, the moral difference between these environments seems insignificant. In such cases, one version of the IA persists. This version establishes the permissibility of choice architecture in circumstances of reliable prediction, but is itself neutral toward available normative directions.

System change and individual behavior change are often conceptualized as contrasting, mutually exclusive strategies for climate change mitigation, with system change usually considered more powerful, direct or urgent. We argue that this alleged duality is misguided and that system change and behavior change are fundamentally co-dependent: system change is often effective to the extent that it promotes individual behavior change and, vice versa, individual behavior change contributes to the critical mass that is needed to spur system change. We map four pathways that link behavior change and system change, driven by consumer activism, consumer demands, policies that address people as part of a community and the provision of collective action arrangements. Together, these pathways illustrate that system and behavior change are often interconnected and suggest promising avenues for developing climate mitigation policies that jointly promote system and behavior change.

Our daily lives are shaped by the digital platforms we engage with, presenting both challenges and opportunities in the pursuit of health and social well-being. Despite extensive public efforts to increase physical activity, sedentary lifestyles and car-dependence persist; often exacerbated by digital apps functioning at odds with these initiatives. With growing urbanization, walking for transportation becomes a feasible way for many Americans to achieve daily activity goals. This work explores the potential of leveraging nudges within digital apps, specifically Google Maps, to encourage walking. I found that displaying walking directions as the default in Google Maps, instead of driving, and complemented by graphics depicting social norms, significantly increased the hypothetical choice to walk — particularly among less active individuals. This underscores the power of digital environments in shaping our choices and outcomes; and highlights the need for us to critically assess digital app design. I advocate for collaboration between ‘big tech’, policymakers, and the public to create digital tools that balance our immediate convenience with long-term health and environmental sustainability goals. Re-envisioning technology’s role in daily life, we can potentially harness its vast influence to foster choices that contribute to both personal well-being and the collective good.