Nearly 2500 years ago, in three different areas of the world, the Yangtze and Yellow River Valleys, the Easter Mediterranean, and the Ganges Valley, conditions were ideal for the emergence of a number of religious traditions, ones which would shape the future of human life to this very day. This 200-year period is called the “Axial Age,” and these doctrines would later become the world’s major religions, including Buddhism, Daoism, Judaism, Christianity, and Islam. The history of this process is well documented, but a key question remains unanswered: why did these similar movements emerge simultaneously?Prior to the Axial Age, in hunter-gatherer societies, early chiefdoms and archaic states, religions were focused on rituals, sacrifices, and respecting taboos, practices that were believed to ensure prosperity. However, the new doctrines were extremely different. Now, “personal transcendence” was valued. Human existence was believed to have a purpose, distinct from the material world, and it lay in a moral existence and control of one’s material desires through moderation, asceticism, and compassion. Central importance was placed on the idea that human beings have a soul that can survive the mortal world; only moderation of these material desires, asceticism, and moral behavior can guarantee the salvation of that soul in the afterlife.In a 2015 publication in Current Biology, researchers in the United States and France, led by Nicolas Baumard, compared the political and economic conditions at that time in order to determine what led to the Axial Age. The religious movements were too innovative to be accounted for through the emergence of large empires, which tended to have organized religions, but lacked the essential focus on asceticism and morality. Drawing on recent evidence from evolutionary psychology that suggested that affluence has a predictable effect on human motivation and reward systems, Baumard and colleagues hypothesized that increased affluence was the major factor in all three areas (the Yangtze and Yellow River Valleys, the Easter Mediterranean, and the Ganges Valley). They used energy capture as a marker of affluence. Quantitative studies had already shown that, at the time, there was a sharp increase in energy capture occurring in exactly those three areas.The researchers tested this link by developing and comparing statistical models in which the likelihood of the emergence of a religion was dependent on a single factor. The models either used the level of affluence or political success as a factor. Their results confirmed that affluence markers provide very good indicators for the emergence of axial religions, whereas political success markers did not.History would agree with these results as well; religious historians have noted that Axial Age movements did not appear in the largest states at the time (eg. Assyria, Egypt, Persia), but in smaller prosperous polities such as Greek city-states, Mahajanapada, and the most developed of Chinese states. However, the authors noted that a number of questions remain. More data on affluence and political success, both in these societies and in other non-Eurasian empires, is needed to test the robustness of the conclusions and would strengthen the model. In addition, though the analysis presented here suggests a general set of conditions, which led to the emergence of these religions, the more specific mechanism remains unknown. Was it a new class of priests or scholars who now had the time and resources to develop more abstract religions? Did economic prosperity lead to an increase in literacy among the believers? Did affluence promote a more cosmopolitan society in which generosity, universality, and self-control were more attractive? The answers to these questions may well explain some of our most basic current beliefs, and shed light on our shared history.Citation: Baumard et al., Increased Affluence Explains the Emergence of Ascetic Wisdoms and Moralizing Religions, Current Biology (2015),