by May Zhang, PhD Student in Evolutionary Anthropology (see profile)
Picture: The Wheel of Reincarnation (photo credit: Ruth Mace)
Could religious beliefs about the afterlife drive group behaviours including warfare and peace? Academic studies of religion have long wondered if different eschatological beliefs (relating to death and the fate of the soul) serve specific social functions and were preferentially adopted by religious groups for their functions. For example, some researchers suspect that beliefs of an imminent apocalypse serve to mobilise revolution against an ‘unjust’ status-quo. Apocalyptic ideologies are featured in all Abrahamic religions and some contemporary millennialist movements. They emphasise that the ‘status-quo’ social orders are filled with injustice and morally bankrupt, and call for an urgent need for renewal and purification. They are often associated with a messianic figure who has the divine authority to redefine doctrines and actions for salvation.
Another common eschatological belief is reincarnation. Commonly featured in Buddhist and Hindu systems, it states that the soul can or will be reborn into another physical body after death. Some scholars suspect reincarnation belief could be used to suppress political activism, by justifying a world filled with inequality and injustice as the outcome of wrongs committed in past lives.
Our research (Basava, Zhang, and Mace, in press), recently published in Nature Human Behaviour, formally tests whether these two eschatological beliefs evolved in parallel with political activism and intergroup violence. In a case study of historical Islamic sects (610 – 1900 CE), we found millennialist belief co-evolved with revolution and religious violence, but most likely the belief was adopted after revolution or religious violence took place, rather than causing these events. We also found that apocalyptic beliefs are associated with, but not necessarily causal to, accelerated group extinction. In our case study, reincarnation beliefs most likely did not co-evolve with passive political attitudes but were implicated in maintaining peace. These results support the idea that political activism and intergroup violence were triggered by sociopolitical contexts, and afterlife ideologies were adopted only afterwards to justify and mobilize collective actions. Political action and afterlife beliefs may then reinforce one another, but the causal relationship is certainly not one-directional.
Phylogenetic Comparative Methods
Similar to biological species, religious groups inherit ideologies and practices from their ancestors, occasionally modify their content, before passing them on to descendent groups. Disputes over ideology or practices can lead to the splitting of one group into multiple lineages, a process parallel to cladogenesis in biological evolution. It is therefore possible to represent Islamic cultural inheritance by reconstructing a phylogeny, calibrated by timings of sect formation and extinction.
Phylogenetic comparative methods (PCMs) are powerful tools for understanding how cultural diversity evolved. A phylogeny shows patterns of hierarchical descent, which can be used to identify independent instances of cultural changes (e.g. gaining or losing an eschatological belief). PCM provides a better-informed guess to questions like: What were marriage customs like in these extinct cultures? Did this architecture style evolve in response to this type of ecology? Did this cultural practice prompt the adoption of that custom, or the other way around? To answer these questions, we need to account for historical contingencies (captured by the phylogeny) and acknowledge the uncertainties in our best-guess answers (using Bayesian inferences).
Based on written historical records, we built a phylogeny representing the ancestry and descent of 75 historical Islamic sects. This included Sunni legal schools as well as various movements which emerged from them, and Shiʿi sects which may have originally split due to leadership disagreements but which developed different practices or beliefs from their parent group. Some theological schools, including Sufism, are not included in our sample despite playing central roles in the development of Islamic philosophical and legal thought. This is because adherents of different Islamic sects could belong to the same or multiple Sufi orders which cannot be captured on the existing phylogeny. Still, our reconstructed phylogeny represents our best attempt to capture the diversity across Islamic doctrinal evolution from the seventh through the twentieth centuries.
PCM has been applied to study religious evolution and found that violent religious ideologies tend to be passed on from ancestral to descendent groups among sixteenth-century Anabaptists1. Although religious beliefs are shaped significantly by the sociopolitical environment, the two eschatological beliefs we examined lie at the core of sect identities and can be traced along the sect ancestry. Islamic scholars also recognise the significance of historical continuity. One scholar of Ibāḍi Islam stated that studying contemporary Wahbi Ibāḍi thought to gain insight into classical Khārijte beliefs is akin to studying modern bird species to better understand extinct dinosaurs.
A phylogenetic tree drawn by Darwin c. 1837
Interdisciplinary Insights
By focusing on the diversity of eschatological beliefs over time and across different historical Islamic groups, our study attempts to incorporate expertise and subject-specific scholarship from the humanities in order to take account of historical contexts and avoid problematic assumptions of homogeneity or essentialism. With such a synthesis, research in this area can contribute to better understandings of how religious groups interact with their natural and social environments, and how variation in the content of religious beliefs may co-evolve with group-level cooperation and conflict in specific ways. Overall, we found no evidence that particular afterlife beliefs drove violent collective action in our sample of historical sects; instead, these beliefs tend to follow rather than create violent circumstances.
Reincarnation and apocalyptic beliefs are of course not unique to Islam or even Abrahamic faiths. Our primary aim was to examine processes of cultural evolution over a family of religious traditions. Whilst our reconstructed phylogeny is certainly not definitive or objective, it represents our best attempt to represent historical relationships based on available sources, which should be subject to revisions and improvement by expertise in different disciplines. Future comparative studies on eschatological beliefs would shed light on the evolutionary relationship between eschatological beliefs and political activism.
This article is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License (CC BY-ND 4.0).
References
1. Matthews, L. J., Edmonds, J., Wildman, W. J. & Nunn, C. L. Cultural inheritance or cultural diffusion of religious violence? A quantitative case study of the Radical Reformation. Religion, Brain & Behavior 3, 3-15 (2013). DOI: 10.1080/2153599X.2012.707388