According to Christian Smith, a sociologist of religion and currently a professor at the University of Notre Dame, the Biological Predisposition Tendency (BPT) is the theory that the “intensities of religiousness will tend to vary across persons according to differences in their biologically grounded genetic and neurological traits” (1).

Several reasons ground religiousness in genetic and neurological traits. First, an ever-expanding quantity of scientific evidence appears to support this hypothesis. Referring to research on identical and fraternal twins raised in shared and unshared environments, one finds that genetic factors (rather than social influences) explain between 19% and 65% of the variation in personal religiousness, depending on the specific religious feature in question (2).

Many studies show that differences in people’s basic personality traits of extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience (called the “Big Five”) are significantly associated with varying levels of personal religiousness (3).

Further, in their attempts to identify the neurological regions of religious activity, neurologists are starting to show that alterations in people’s neurological functioning bring with them changes in their personal religiousness (4). 

Smith says that more research in these areas is needed before anyone can be confident in the reliability and generalizability of such findings. The current studies do, however, provide good reasons to believe that differences in people’s religiousness are partly shaped by genetic, biochemical, and neurological factors.

Smith contends that the BPT perspective is important because “All things social are linked to and interact with the natural world—biology, chemistry, and human brains. We can only improve our understanding of religion in a realist mode if we investigate those connections” (5).

Smith says that he is not advocating genetic determinism in the form of a “religion gene” that inevitably determines one’s personal religiousness because reality is more complex than genetic determinism can account for, especially because the downward causal powers of the social, environmental, and personal factors shape lower-level genetic and biochemical processes. It is important, nonetheless, to understand any possible biological elements affecting religious practice.

Smith’s BPT theory must be viewed as an addition to several other factors partially explaining religiosity in human beings. Other factors include the desire for humans to propitiate superhuman powers for assistance, the ten features of the human’s advanced cognitive faculties, and the Vulnerable Religious Demand tendency.

References

1. Smith, Christian. “Why Are Humans Religious?” In Religion: What It Is, How It Works, and Why It Matters, 190-233. Princeton University Press. 

2. D’Onofrio, Brian., Eaves, Lindon., Murrelle, Lenn., Maes, Hermine., and Spilka, Bernard. 1999. “Understanding Biological and Social Influences on Religious Affiliation, Attitudes, and Behavior.” Journal of Personality 67: 953-984; Bradshaw, Matt., and Ellison, Christopher. 2008. “Do Genetic Factors Influence Religious Life?” Journal for the Scientific Study of Religion 47: 529-544.

3. Saroglou, V. 2002. “Religion and the Five Factors of Personality.” Personality and Individual Differences 32:15-25; McCollough, Michael., Tsand, Jo-Ann., and Brion, Sharon. 2003. “Personality Traits in Adolescence as Predictors of Religiousness in Early Adulthood.” Personality and Social Psychology Bulletin 29:980-991; Francis, L., Argyle, M., and Jackson C. 2004. “Primary Personality Trait Correlates of Religious Practice and Orientation.” Personality and Individual Differences 36:61-73; Wink, Paul., Ciciolla, Lucia., Dillon, Michele., and Tracy, Allison. 2007. “Religiousness, Spiritual Seeking, and Personality: Findings from a Longitudinal Study.” Journal of Personality 75:1051-1070; Henningsgaard, Jude., and Arnau, Randolph. 2008. “Relationships between Religiosity, Spirituality, and Personality.” Personality and Individual Differences 45:703-708; Ladenhauf, H., Moazedi, M., Wallner-Liebmann, S., and Fink, A. 2010. “Dimensions of Religious/Spiritual Well-being and their Relation to Personality and Psychological Well-being.” Personality and Individual Differences 49: 192-197.

4. Muramoto, Osamu. 2004. “The Role of Medial Prefrontal Cortex in Human Religious Activity.” Medical Hypotheses 62:479-485; Previc, Fred. 2006. “The Role of the Extrapersonal Brain Systems in Religious Activity.” Consciousness and Cognition 15:500-539; Devinsky, O., and Lai, G. 2008. “Spirituality and Religion in Epilepsy.” Epilepsy and Behavior 12:636–643. Butler, Paul., McNamara, Patrick., and Durson, Raymond. 2011. “Side of Onset in Parkinson’s Disease and Alterations in Religiosity.” Behavioral Neurology 24:133-141; Johnstone, Brick., Bodling, Angela., Cohen, Dan., Christ, Shawn., and Wegrzyn, Andrew. 2012. “Right Parietal Lobe- Related ‘Selflessness’ as the Neuropsychological Basis of Spiritual Transcendence.” International Journal for the Psychology of Religion 22:267-284; McCrae, Niall., and Whitley, Rob. 2014. “Exaltation in Temporal Lobe Epilepsy.” Journal of Medical Humanities 35:241-255.

5. Hills, P., Francis, L., Argyle, M., and Jackson, C. 2004. “Primary Personality Trait Correlates of Religious Practice and Orientation.” Personality and Individual Differences 36:61-73; Henningsgaard, Jude., and Arnau, Randolph. 2008. Ibid. p. 703-708.