Cultural similarity among coreligionists within and between countries.

Cultural evolutionary theories suggest that world religions have consolidated beliefs, values, and practices within a superethnic cultural identity. It follows that affiliation with religious traditions would be reliably associated with global variation in cultural traits. To test this hypothesis, we measured cultural distance between religious groups within and between countries, using the Cultural Fixation Index ([Formula: see text]) applied to the World Values Survey (88 countries, n = 243,118). Individuals who shared a religious tradition and level of commitment to religion were more culturally similar, both within and across countries, than those with different affiliations and levels of religiosity, even after excluding overtly religious values. Moreover, distances between denominations within a world religion echoed shared historical descent. Nonreligious individuals across countries also shared cultural values, offering evidence for the cultural evolution of secularization. While nation-states were a stronger predictor of cultural traits than religious traditions, the cultural similarity of coreligionists remained robust, controlling for demographic characteristics, geographic and linguistic distances between groups, and government restriction on religion. Together, results reveal the pervasive cultural signature of religion and support the role of world religions in sustaining superordinate identities that transcend geographical boundaries.

Thinking About God Encourages Prosociality Toward Religious Outgroups: A Cross-Cultural Investigation.

Most humans believe in a god or gods, a belief that may promote prosociality toward coreligionists. A critical question is whether such enhanced prosociality is primarily parochial and confined to the religious ingroup or whether it extends to members of religious outgroups. To address this question, we conducted field and online experiments with Christian, Muslim, Hindu, and Jewish adults in the Middle East, Fiji, and the United States (N = 4,753). Participants were given the opportunity to share money with anonymous strangers from different ethno-religious groups. We manipulated whether they were asked to think about their god before making their choice. Thinking about God increased giving by 11% (4.17% of the total stake), an increase that was extended equally to ingroup and outgroup members. This suggests that belief in a god or gods may facilitate intergroup cooperation, particularly in economic transactions, even in contexts with heightened intergroup tension.

Moralistic gods, supernatural punishment and the expansion of human sociality.

Since the origins of agriculture, the scale of human cooperation and societal complexity has dramatically expanded. This fact challenges standard evolutionary explanations of prosociality because well-studied mechanisms of cooperation based on genetic relatedness, reciprocity and partner choice falter as people increasingly engage in fleeting transactions with genetically unrelated strangers in large anonymous groups. To explain this rapid expansion of prosociality, researchers have proposed several mechanisms. Here we focus on one key hypothesis: cognitive representations of gods as increasingly knowledgeable and punitive, and who sanction violators of interpersonal social norms, foster and sustain the expansion of cooperation, trust and fairness towards co-religionist strangers. We tested this hypothesis using extensive ethnographic interviews and two behavioural games designed to measure impartial rule-following among people (n = 591, observations = 35,400) from eight diverse communities from around the world: (1) inland Tanna, Vanuatu; (2) coastal Tanna, Vanuatu; (3) Yasawa, Fiji; (4) Lovu, Fiji; (5) Pesqueiro, Brazil; (6) Pointe aux Piments, Mauritius; (7) the Tyva Republic (Siberia), Russia; and (8) Hadzaland, Tanzania. Participants reported adherence to a wide array of world religious traditions including Christianity, Hinduism and Buddhism, as well as notably diverse local traditions, including animism and ancestor worship. Holding a range of relevant variables constant, the higher participants rated their moralistic gods as punitive and knowledgeable about human thoughts and actions, the more coins they allocated to geographically distant co-religionist strangers relative to both themselves and local co-religionists. Our results support the hypothesis that beliefs in moralistic, punitive and knowing gods increase impartial behaviour towards distant co-religionists, and therefore can contribute to the expansion of prosociality.

Moralizing gods, impartiality and religious parochialism across 15 societies.

The emergence of large-scale cooperation during the Holocene remains a central problem in the evolutionary literature. One hypothesis points to culturally evolved beliefs in punishing, interventionist gods that facilitate the extension of cooperative behaviour toward geographically distant co-religionists. Furthermore, another hypothesis points to such mechanisms being constrained to the religious ingroup, possibly at the expense of religious outgroups. To test these hypotheses, we administered two behavioural experiments and a set of interviews to a sample of 2228 participants from 15 diverse populations. These populations included foragers, pastoralists, horticulturalists, and wage labourers, practicing Buddhism, Christianity, and Hinduism, but also forms of animism and ancestor worship. Using the Random Allocation Game (RAG) and the Dictator Game (DG) in which individuals allocated money between themselves, local and geographically distant co-religionists, and religious outgroups, we found that higher ratings of gods as monitoring and punishing predicted decreased local favouritism (RAGs) and increased resource-sharing with distant co-religionists (DGs). The effects of punishing and monitoring gods on outgroup allocations revealed between-site variability, suggesting that in the absence of intergroup hostility, moralizing gods may be implicated in cooperative behaviour toward outgroups. These results provide support for the hypothesis that beliefs in monitoring and punitive gods help expand the circle of sustainable social interaction, and open questions about the treatment of religious outgroups.

Theodiversity.

Humanity is teeming with breathtaking theodiversity--in religious beliefs, behaviors, and traditions, as well as in various intensities and forms of disbelief. Yet the origins and consequences of this diversity have received limited attention in psychology. I first describe how evolved psychological processes that influence and respond to cultural evolutionary trajectories generate and channel religious diversity. Next, I explore how theodiversity in turn shapes human psychology, and discuss three cultural dimensions of religious diversity in relation to psychological processes: (a) the cultural shift from small foraging bands and their local religious practices and beliefs to large and complex groups and their world religions, (b) cultural variability among world religions, and (c) secularization and the ensuing cultural divide between religious and nonreligious societies and subcultures. The contributions of psychology to the scientific study of religion will increase with a deeper understanding of theodiversity.

Religious Priming: A Meta-Analysis With a Focus on Prosociality.

Priming has emerged as a valuable tool within the psychological study of religion, allowing for tests of religion's causal effect on a number of psychological outcomes, such as prosocial behavior. As the literature has grown, questions about the reliability and boundary conditions of religious priming have arisen. We use a combination of traditional effect-size analyses, p-curve analyses, and adjustments for publication bias to evaluate the robustness of four types of religious priming (Analyses 1-3), review the empirical evidence for religion's effect specifically on prosocial behavior (Analyses 4-5), and test whether religious-priming effects generalize to individuals who report little or no religiosity (Analyses 6-7). Results across 93 studies and 11,653 participants show that religious priming has robust effects across a variety of outcome measures-prosocial measures included. Religious priming does not, however, reliably affect non-religious participants-suggesting that priming depends on the cognitive activation of culturally transmitted religious beliefs.

The cultural evolution of prosocial religions.

We develop a cultural evolutionary theory of the origins of prosocial religions and apply it to resolve two puzzles in human psychology and cultural history: (1) the rise of large-scale cooperation among strangers and, simultaneously, (2) the spread of prosocial religions in the last 10-12 millennia. We argue that these two developments were importantly linked and mutually energizing. We explain how a package of culturally evolved religious beliefs and practices characterized by increasingly potent, moralizing, supernatural agents, credible displays of faith, and other psychologically active elements conducive to social solidarity promoted high fertility rates and large-scale cooperation with co-religionists, often contributing to success in intergroup competition and conflict. In turn, prosocial religious beliefs and practices spread and aggregated as these successful groups expanded, or were copied by less successful groups. This synthesis is grounded in the idea that although religious beliefs and practices originally arose as nonadaptive by-products of innate cognitive functions, particular cultural variants were then selected for their prosocial effects in a long-term, cultural evolutionary process. This framework (1) reconciles key aspects of the adaptationist and by-product approaches to the origins of religion, (2) explains a variety of empirical observations that have not received adequate attention, and (3) generates novel predictions. Converging lines of evidence drawn from diverse disciplines provide empirical support while at the same time encouraging new research directions and opening up new questions for exploration and debate.

Parochial prosocial religions: Historical and contemporary evidence for a cultural evolutionary process.

In our response to the 27 commentaries, we refine the theoretical claims, clarify several misconceptions of our framework, and explore substantial disagreements. In doing so, we (1) show that our framework accommodates multiple historical scenarios; (2) debate the historical evidence, particularly about "pre-Axial" religions; (3) offer important details about cultural evolutionary theory; (4) clarify the term prosociality; and (4) discuss proximal mechanisms. We review many interesting extensions, amplifications, and qualifications of our approach made by the commentators.

Gods are watching and so what? Moralistic supernatural punishment across 15 cultures.

Psychological and cultural evolutionary accounts of human sociality propose that beliefs in punitive and monitoring gods that care about moral norms facilitate cooperation. While there is some evidence to suggest that belief in supernatural punishment and monitoring generally induce cooperative behaviour, the effect of a deity's explicitly postulated moral concerns on cooperation remains unclear. Here, we report a pre-registered set of analyses to assess whether perceiving a locally relevant deity as moralistic predicts cooperative play in two permutations of two economic games using data from up to 15 diverse field sites. Across games, results suggest that gods' moral concerns do not play a direct, cross-culturally reliable role in motivating cooperative behaviour. The study contributes substantially to the current literature by testing a central hypothesis in the evolutionary and cognitive science of religion with a large and culturally diverse dataset using behavioural and ethnographically rich methods.

Reminders of secular authority reduce believers' distrust of atheists.

Atheists have long been distrusted, in part because they do not believe that a watchful, judging god monitors their behavior. However, in many parts of the world, secular institutions such as police, judges, and courts are also potent sources of social monitoring that encourage prosocial behavior. Reminders of such secular authority could therefore reduce believers' distrust of atheists. In our experiments, participants who watched a video about police effectiveness (Experiment 1) or were subtly primed with secular-authority concepts (Experiments 2-3) expressed less distrust of atheists than did participants who watched a control video or were not primed, respectively. We tested three distinct alternative explanations for these findings. Compared with control participants, participants primed with secular-authority concepts did not exhibit reduced general prejudice against out-groups (Experiment 1), prejudice reactions associated with functional threats that particular out-groups are perceived to pose (specifically, viewing gays with disgust; Experiment 2), or general distrust of out-groups (Experiment 3). These findings contribute to theory regarding both the psychological bases of prejudices and the psychological functions served by gods and governments.

How cultural learning and cognitive biases shape religious beliefs.

What explains the ubiquity and diversity of religions around the world? Widespread cognitive tendencies, including mentalizing and intuitive thinking, offer part of the explanation for recurrent features of religion, and individual differences in religious commitments. However, vast diversity in religious beliefs points to the importance of the cultural context in which religious beliefs are transmitted. Cultural evolutionary theory provides the basis of a unified explanation for how cognition and culture interact to shape religious beliefs, in ways that are uniquely adapted to local ecological pressures. These insights lay the groundwork for future research regarding how cultural learning interacts with other evolved aspects of human psychology to generate the recurrent and the diverse forms of religious commitments observed around the world.

Cognitive Pathways to Belief in Karma and Belief in God.

Supernatural beliefs are ubiquitous around the world, and mounting evidence indicates that these beliefs partly rely on intuitive, cross-culturally recurrent cognitive processes. Specifically, past research has focused on humans' intuitive tendency to perceive minds as part of the cognitive foundations of belief in a personified God-an agentic, morally concerned supernatural entity. However, much less is known about belief in karma-another culturally widespread but ostensibly non-agentic supernatural entity reflecting ethical causation across reincarnations. In two studies and four high-powered samples, including mostly Christian Canadians and mostly Hindu Indians (Study 1, N = 2,006) and mostly Christian Americans and Singaporean Buddhists (Study 2, N = 1,752), we provide the first systematic empirical investigation of the cognitive intuitions underlying various forms of belief in karma. We used path analyses to (a) replicate tests of the previously documented cognitive predictors of belief in God, (b) test whether this same network of variables predicts belief in karma, and (c) examine the relative contributions of cognitive and cultural variables to both sets of beliefs. We found that cognitive tendencies toward intuitive thinking, mentalizing, dualism, and teleological thinking predicted a variety of beliefs about karma-including morally laden, non-agentic, and agentic conceptualizations-above and beyond the variability explained by cultural learning about karma across cultures. These results provide further evidence for an independent role for both culture and cognition in supporting diverse types of supernatural beliefs in distinct cultural contexts.

The weirdest people in the world?

Behavioral scientists routinely publish broad claims about human psychology and behavior in the world's top journals based on samples drawn entirely from Western, Educated, Industrialized, Rich, and Democratic (WEIRD) societies. Researchers - often implicitly - assume that either there is little variation across human populations, or that these "standard subjects" are as representative of the species as any other population. Are these assumptions justified? Here, our review of the comparative database from across the behavioral sciences suggests both that there is substantial variability in experimental results across populations and that WEIRD subjects are particularly unusual compared with the rest of the species - frequent outliers. The domains reviewed include visual perception, fairness, cooperation, spatial reasoning, categorization and inferential induction, moral reasoning, reasoning styles, self-concepts and related motivations, and the heritability of IQ. The findings suggest that members of WEIRD societies, including young children, are among the least representative populations one could find for generalizing about humans. Many of these findings involve domains that are associated with fundamental aspects of psychology, motivation, and behavior - hence, there are no obvious a priori grounds for claiming that a particular behavioral phenomenon is universal based on sampling from a single subpopulation. Overall, these empirical patterns suggests that we need to be less cavalier in addressing questions of human nature on the basis of data drawn from this particularly thin, and rather unusual, slice of humanity. We close by proposing ways to structurally re-organize the behavioral sciences to best tackle these challenges.

How strongly do moral character inferences predict forecasts of the future? Testing the moderating roles of transgressor age, implicit personality theories, and belief in karma.

Three studies (total N = 1486) investigated how inferences about a person's current moral character guide forecasts about that person's future moral character and future misfortunes, and tested several plausible moderating variables. Inferences about current moral character related (very strongly) to forecasts about future moral character and also (less strongly) to forecasts about future misfortunes. These relationships were moderated by two variables: Relations between inferences and forecasts were somewhat weaker when perceivers made judgments about children, compared to judgments about adults, and relations between character inferences and forecasts about misfortunes were somewhat stronger among perceivers who more strongly believed in karma. In contrast, results provided no evidence of any moderating effects due to perceivers' beliefs about the stability of moral dispositions (i.e., implicit personality theories). These results show how dispositional inferences, moral judgments, and beliefs about karmic justice interact to shape forecasts about the future.

Religion and support for suicide attacks.

In four studies carried out across different cultural, religious, and political contexts, we investigated the association between religion and popular support for suicide attacks. In two surveys of Palestinians and one cognitive priming experiment with Israeli settlers, prayer to God, an index of religious devotion, was unrelated to support for suicide attacks. Instead, attendance at religious services, thought to enhance coalitional commitment, positively predicted support for suicide attacks. In a survey of six religions in six nations, regular attendance at religious services positively predicted a combination of willing martyrdom and out-group hostility, but regular prayer did not. Implications for understanding the role of religion in suicide attacks are discussed.

Weighing outcome vs. intent across societies: How cultural models of mind shape moral reasoning.

Mental state reasoning has been theorized as a core feature of how we navigate our social worlds, and as especially vital to moral reasoning. Judgments of moral wrong-doing and punish-worthiness often hinge upon evaluations of the perpetrator's mental states. In two studies, we examine how differences in cultural conceptions about how one should think about others' minds influence the relative importance of intent vs. outcome in moral judgments. We recruit participation from three societies, differing in emphasis on mental state reasoning: Indigenous iTaukei Fijians from Yasawa Island (Yasawans) who normatively avoid mental state inference in favor of focus on relationships and consequences of actions; Indo-Fijians who normatively emphasize relationships but do not avoid mental state inference; and North Americans who emphasize individual autonomy and interpreting others' behaviors as the direct result of mental states. In study 1, Yasawan participants placed more emphasis on outcome than Indo-Fijians or North Americans by judging accidents more harshly than failed attempts. Study 2 tested whether underlying differences in the salience of mental states drives study 1 effects by inducing Yasawan and North American participants to think about thoughts vs. actions before making moral judgments. When induced to think about thoughts, Yasawan participants shifted to judge failed attempts more harshly than accidents. Results suggest that culturally-transmitted concepts about how to interpret the social world shape patterns of moral judgments, possibly via mental state inference.

The Content and Correlates of Belief in Karma Across Cultures.

Karmic beliefs, centered on the expectation of ethical causation within and across lifetimes, appear in major world religions as well as spiritual movements around the world, yet they remain an underexplored topic in psychology. In three studies, we assessed the psychological predictors of Karmic beliefs among participants from culturally and religiously diverse backgrounds, including ethnically and religiously diverse students in Canada, and broad national samples of adults from Canada, India, and the United States (total N = 8,996). Belief in Karma is associated with, but not reducible to, theoretically related constructs including belief in a just world, belief in a moralizing God, religious participation, and cultural context. Belief in Karma also uniquely predicts causal attributions for misfortune. Together, these results show the value of measuring explicit belief in Karma in cross-cultural studies of justice, religion, and social cognition.