High economic inequality is linked to greater moralization.

Throughout the 21st century, economic inequality is predicted to increase as we face new challenges, from changes in the technological landscape to the growing climate crisis. It is crucial we understand how these changes in inequality may affect how people think and behave. We propose that economic inequality threatens the social fabric of society, in turn increasing moralization-that is, the greater tendency to employ or emphasize morality in everyday life-as an attempt to restore order and control. Using longitudinal data from X, formerly known as Twitter, our first study demonstrates that high economic inequality is associated with greater use of moral language online (e.g. the use of words such as "disgust", "hurt", and "respect'). Study 2 then examined data from 41 regions around the world, generally showing that higher inequality has a small association with harsher moral judgments of people's everyday actions. Together these findings demonstrate that economic inequality is linked to the tendency to see the world through a moral lens.

Testing the bounds of compassion in young children.

Extensive research shows that, under the right circumstances, children are highly prosocial. Extending an already published paradigm, we aimed here to determine what factors might facilitate and inhibit compassionate behaviour. Across five experiments (N = 285), we provide new insight into the bounds of 4- to 5-year-old children's compassionate behaviour. In the first three experiments, we varied cost of compassion by changing the reward (Study 1), using explicit instructions (Study 2) and ownership (Study 3). In the final two experiments, we varied the target of the compassionate behaviour, examining adults compared with puppet targets (Study 4), and whether the target was an in-group member (Study 5). We found strong evidence that cost reduces compassionate responding. By contrast, the recipient of compassion did not appear to influence responding: children were equally likely to help a human adult and a puppet, and an in-group member and neutral agent. These findings demonstrate that for young children, personal cost appears to be a greater inhibitor to compassionate responding than who compassion is directed toward.

Social mindfulness predicts concern for nature and immigrants across 36 nations.

People cooperate every day in ways that range from largescale contributions that mitigate climate change to simple actions such as leaving another individual with choice - known as social mindfulness. It is not yet clear whether and how these complex and more simple forms of cooperation relate. Prior work has found that countries with individuals who made more socially mindful choices were linked to a higher country environmental performance - a proxy for complex cooperation. Here we replicated this initial finding in 41 samples around the world, demonstrating the robustness of the association between social mindfulness and environmental performance, and substantially built on it to show this relationship extended to a wide range of complex cooperative indices, tied closely to many current societal issues. We found that greater social mindfulness expressed by an individual was related to living in countries with more social capital, more community participation and reduced prejudice towards immigrants. Our findings speak to the symbiotic relationship between simple and more complex forms of cooperation in societies.

Promoting prosocial behavior in an unequal world.

Amid a global pandemic and the climate crisis, there is an increasing need to understand how to promote largescale, coordinated action between different groups. Yet certain factors such as inequality can hinder cooperation. We aimed to establish how to orient groups toward a superordinate goal when they have unequal resources. Participants were divided into two 'countries' and asked to assemble LEGO bricks into food (by building pieces in a certain order) to prevent starvation among 'the people'. One 'country' had few LEGO bricks whereas the other had an abundance, and the only way to maximize food creation was for the groups to work together. We assessed the efficacy of three diverse interventions on superordinate behavior and attitudes: compassion meditation training (Study 1), lower inequality (Study 2), and the introduction of a pro-sharing group norm by a confederate (Study 3). Compassion meditation training and altering the degree of inequality between groups did not have a clear effect on collaborative action. Only the introduction of a pro-sharing group norm enhanced sharing behavior, made participants feel more cooperative and reduced fears of being compassionate toward others. Our findings speak to the importance of leadership in promoting coordinated action to address challenges that face the superordinate group.

How economic inequality affects prosocial behavior in children across development.

Research has linked economically unequal environments to lower prosocial behavior in adults. However, we know little about how inequality affects children's prosociality. Here, 4- to 9-year-old children (N = 128) played a series of games with several puppets where points were awarded. The distribution of points was characterized by either high inequality or low inequality. Children's donation behavior (i.e., the number of stickers they donated to a poor child), resource division behavior (i.e., how they divided extra points among poor and rich puppets), and fairness perceptions (i.e., how fair they perceived the game to be) were measured in response. Although the experimental manipulation of inequality did not affect children's donations, exploratory analyses revealed that higher inequality in children's home suburb was linked to lower donation rates. Furthermore, with age, children distributed points with increasing concern for poorer individuals, and negative judgments of the inequality were linked to distributing resources to poorer individuals. Here we present the first comprehensive analysis of children's prosocial reactions to high and low inequality across development.

The effect of economic inequality on young children's prosocial decision-making.

An emerging body of literature has documented the negative implications high economic inequality can have on children's social and cognitive development. However, little experimental research has directly addressed how wealth discrepancies impact the way children treat others. The current study thus aimed to address the implications of economic inequality on prosocial decision-making in children prior to commencing formal schooling. Using a novel experimental paradigm, we immersed 4-year-old children (N = 58) in a series of games where they played against puppets for rewards. During this process, children were exposed to resource allocations featuring either high inequality or low inequality. We subsequently measured children's donation behaviour, resource division behaviour, and fairness perceptions. As predicted, children were less altruistic when exposed to high inequality compared to low inequality. Contrary to predictions, there was no difference in resource division behaviour or fairness perceptions. This study documents for the first time that exposure to environmental inequality, even if brief and in a controlled experimental setting, can influence young children's prosocial decision-making. Statement of contribution What is already known on the subject? Adults tend to be less prosocial towards others after experiencing high economic inequality. Young children understand when outcomes are unequal. Young children also have a rudimentary understanding of what is fair. What does this study adds? A novel experimental design was utilized to immerse children in a safe experimental economy. Pre-schoolers are less altruistic after experiencing high inequality compared to low inequality. Children did not attempt to adjust prior inequalities in their resource division behaviour.

It's in the bag: mobile containers in human evolution and child development.

Mobile containers are a keystone human innovation. Ethnographic data indicate that all human groups use containers such as bags, quivers and baskets, ensuring that individuals have important resources at the ready and are prepared for opportunities and threats before they materialize. Although there is speculation surrounding the invention of carrying devices, the current hard archaeological evidence only reaches back some 100,000 years. The dearth of ancient evidence may reflect not only taphonomic processes, but also a lack of attention to these devices. To begin investigating the origins of carrying devices we focus on exploring the basic cognitive processes involved in mobile container use and report an initial study on young children's understanding and deployment of such devices. We gave 3- to 7-year-old children (N = 106) the opportunity to spontaneously identify and use a basket to increase their own carrying capacity and thereby obtain more resources in the future. Performance improved linearly with age, as did the likelihood of recognizing that adults use mobile carrying devices to increase carrying capacity. We argue that the evolutionary and developmental origins of mobile containers reflect foundational cognitive processes that enable humans to think about their own limits and compensate for them.