Person:

Henrich, Joseph

A growing body of evidence suggests that humans are a new kind of animal—a product of genetic information from our parents and cultural information from our societies. This “Dual Inheritance Theory”, grounded in the biological sciences, offers a deeper understanding of human origins and a formal theoretical framework for unifying the social sciences. Such a theory has remained elusive with attempts dismissed as “physics envy”. We argue that if social scientists are to envy or emulate another science, that science ought to be biology, whose staggering success is in large part due to its synthesis under a formal evolutionary theoretical framework. Dual Inheritance Theory makes several predictions for the psychological foundations of cultural evolution, with implications for our psychology and behaviour more broadly. These foundations give us the mechanisms of cultural evolutionary theory, which offers a formal framework for understanding the evolution of institutions and the co-evolving cultural norms. These often-invisible cultural pillars on which institutions rest are the key to understanding why institutions, such as democracy, often succeed in one cultural context, but fail in another, with implications for economics, politics, and law. An understanding of how cultural traits interact with other cultural traits combined with large databases of historical knowledge may offer new approaches to the study of history. The general approach of deriving and testing these predictions with tools from the biological and social sciences is a crucial, but ignored aspect of the replication crisis and a model for how to move toward a more general theory of human behaviour.

Does the experience of war increase people’s religiosity? Much evidence supports the idea that particular religious beliefs and ritual forms can galvanize social solidarity and motivate in-group cooperation, thus facilitating a wide range of collective behaviors including—but not limited to— peaceful collective resistance to aggression and/or further violent conflicts. However, little work has focused on whether violent conflict, in turn, might fuel greater religious participation. Here, we analyze survey data from 1,709 individuals in three post-conflict societies—Uganda, Sierra Leone and Tajikistan. The nature of these conflicts allows us to infer, and statistically verify, that individuals were quasi-randomly afflicted with different intensities of war experience—thus potentially providing a natural experiment. We then show that those with greater exposure to these wars were more likely to participate in Christian or Muslim religious groups and rituals, even several years after the conflict. The results are robust to a wide range of control variables and statistical checks, and hold even when we compare only individuals from the same communities, ethnic groups and religions.