Skip to main content
SpringerLink
Log in

Are Moral Intuitions Heritable?

  • Published:
Human Nature Aims and scope Submit manuscript

Abstract

Two prominent theoretical frameworks in moral psychology, Moral Foundations and Dual Process Theory, share a broad foundational assumption that individual differences in human morality are dispositional and in part due to genetic variation. The only published direct test of heritability, however, found little evidence of genetic influences on moral judgments using instrumentation approaches associated with Moral Foundations Theory. This raised questions about one of the core assumptions underpinning intuitionist theories of moral psychology. Here we examine the heritability of moral psychology using the moral dilemmas approach commonly used in Dual Process Theory research. Using such measures, we find consistent and significant evidence of heritability. These findings have important implications not only for understanding which measures do, or do not, tap into the genetically influenced aspects of moral decision-making, but in better establishing the utility and validity of different intuitionist theoretical frameworks and the source of why people differ in those frameworks.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Data Availability

https://doi.org/10.7910/DVN/2NUL5A

Notes

  1. These findings have attracted substantial attention. We therefore provide a detailed reanalysis of the heritability of MFQ’s in the supplementary information accompanying this article (ESM §4). In these reanalyses we deliberately attempt to inflate the heritability of moral foundations by ignoring the proposed five-factor structure of the data, removing items for which DZ co-twin correlations are at least as large as the MZ co-twins (this ensures finding at least some heritability), and ignoring sex differences. After these heroic modifications to MFT and sidestepping standard methodical guidelines, we find at best genetic influences of .12 to .14 in the 10-item MFQ, and .23–.24 in the 20-item MFQ. Even then, tests in all cases find that models without genetic influences fit just as well as including them does.

  2. Kahane et al. (2015) also report that there is little relationship between DPT’s sacrificial hypothetical and other externally valid utilitarian beliefs.

References

  • Bailey, J. M., Kirk, K. M., Zhu, G., Dunne, M. P., & Martin, N. G. (2000). Do individual differences in sociosexuality represent genetic or environmentally contingent strategies? Evidence from the Australian twin registry. Journal of Personality and Social Psychology, 78(3), 537–545.

    Article  Google Scholar 

  • Barnett, S. (1983). Humanity and natural selection. Ethology and Sociobiology, 4(1), 35–51.

    Article  Google Scholar 

  • Boehm, C. (2012). Moral origins: The evolution of virtue, altruism, and shame. Basic Books.

  • Bostyn, D. H., Sevenhant, S., & Roets, A. (2018). Of mice, men, and trolleys: Hypothetical judgment versus real-life behavior in trolley-style moral dilemmas. Psychological Science, 29(7), 1084–1093.

    Article  Google Scholar 

  • Brandt, M. J., & Wetherell, G. A. (2012). What attitudes are moral attitudes? The case of attitude heritability. Social Psychological and Personality Science, 3(2), 172–179.

    Article  Google Scholar 

  • Christensen, J. F., Flexas, A., Calabrese, M., Gut, N. K., & Gomila, A. (2014). Moral judgment reloaded: A moral dilemma validation study. Frontiers in Psychology, 5, 607.

    Article  Google Scholar 

  • Churchland, P. S. (2018). Braintrust: What neuroscience tells us about morality. Princeton: Princeton University Press.

    Book  Google Scholar 

  • Coventry, W. L., & Keller, M. C. (2005). Estimating the extent of parameter bias in the classical twin design: A comparison of parameter estimates from extended twin-family and classical twin designs. Twin Research and Human Genetics, 8(03), 214–223.

    Article  Google Scholar 

  • Cushman, F. (2013). Action, outcome, and value: A dual-system framework for morality. Personality and Social Psychology Review, 17(3), 273–292.

    Article  Google Scholar 

  • Cushman, F., Young, L., & Hauser, M. (2006). The role of conscious reasoning and intuition in moral judgment: Testing three principles of harm. Psychological Science, 17(12), 1082–1089.

    Article  Google Scholar 

  • Darwin, C. (1859). On the origin of species by means of natural selection, or, the preservation of favoured races in the struggle for life. London: J. Murray.

    Book  Google Scholar 

  • Dunkel, C. S., Nedelec, J. L., & van der Linden, D. (2018). Using monozygotic twin differences to examine the relationship between parental affection and personality: A life history account. Evolution and Human Behavior, 39(1), 52–58.

    Article  Google Scholar 

  • Eaves, L. J. (1977). Inferring the causes of human variation. Journal of the Royal Statistical Society, A, 140(3), 324–355.

    Article  Google Scholar 

  • Evans, J. S. B. (2008). Dual-processing accounts of reasoning, judgment, and social cognition. Annual Review of Psychology, 59, 255–278.

    Article  Google Scholar 

  • Foot, P. (1967). The problem of abortion and the doctrine of double effect. Oxford Review, 5, 5-15. Reprinted in Virtues and Vices and Other Essays in Moral Philosophy (Oxford: Blackwell, 1978).

  • Friesen, A. (2019). Generational change? The effects of family, age, and time on moral foundations. The Forum, 17(1), 121–140.

    Article  Google Scholar 

  • Graham, J., Haidt, J., & Nosek, B. (2009). Liberals and conservatives rely on different sets of moral foundations. Journal of Personality and Social Psychology, 96(5), 1029–1046.

    Article  Google Scholar 

  • Graham, J., Nosek, B. A., Haidt, J., Iyer, R., Koleva, S., & Ditto, P. H. (2011). Mapping the moral domain. Journal of Personality and Social Psychology, 10(2), 366–385.

    Article  Google Scholar 

  • Greene, J. D. (2013). Moral tribes: Emotion, reason, and the gap between us and them. London: Atlantic Books.

    Google Scholar 

  • Greene, J. D., & Haidt, J. (2002). How (and where) does moral judgment work? Trends in Cognitive Sciences, 6(12), 517–523.

    Article  Google Scholar 

  • Greene, J. D., Sommerville, R. B., Nystrom, L. E., Darley, J. M., & Cohen, J. D. (2001). An fMRI investigation of emotional engagement in moral judgment. Science, 293(5537), 2105–2108.

    Article  Google Scholar 

  • Greene, J. D., Cushman, F. A., Stewart, L. E., Lowenberg, K., Nystrom, L. E., & Cohen, J. D. (2009). Pushing moral buttons: The interaction between personal force and intention in moral judgment. Cognition, 111(3), 364–371.

    Article  Google Scholar 

  • Haidt, J. (2001). The emotional dog and its rational tail: A social intuitionist approach to moral judgment. Psychological Review, 108(4), 814–834.

    Article  Google Scholar 

  • Haidt, J. (2012). The righteous mind: Why good people are divided by politics and religion. New York: Vintage Books.

    Google Scholar 

  • Haidt, J. (2017). Are moral foundations heritable? Probably. https://righteousmind.com/are-moral-foundations-heritable-probably/

  • Haidt, J., & Joseph, C. (2011). How moral foundations theory succeeded in building on sand: A response to Suhler and Churchland. Journal of Cognitive Neuroscience, 23(9), 2117–2122.

    Article  Google Scholar 

  • Hatemi, P. K., Funk, C. L., Medland, S. E., Maes, H. M., Silberg, J. L., Martin, N. G., & Eaves, L. J. (2009). Genetic and environmental transmission of political attitudes over a life time. The Journal of Politics, 71(03), 1141–1156.

    Article  Google Scholar 

  • Hatemi, P. K., Smith, K. B., Alford, J. R., Martin, N. G., & Hibbing, J. R. (2015). The genetic and environmental foundations of political, psychological, social, and economic behaviors: A panel study of twins and families. Twin Research and Human Genetics, 18, 243–255.

    Article  Google Scholar 

  • Hatemi, P. K., Crabtree, C., & Smith, K. B. (2019). Ideology justifies morality: Political beliefs predict moral foundations. Am J Pol Sci, 63(4), 788–806.

    Article  Google Scholar 

  • Hauser, M. D. (2006). Moral minds: The nature of right and wrong. New York: HarperCollins.

    Google Scholar 

  • Iurino, K., & Saucier, G. (2020). Testing measurement invariance of the Moral Foundations Questionnaire across 27 countries. Assessment, 27(2), 365–372.

  • Jinks, J. L., & Fulker, D. W. (1970). Comparison of the biometrical genetical, MAVA, and classical approaches to the analysis of human behavior. Psychological Bulletin, 73(5), 311–349.

    Article  Google Scholar 

  • Kahane, G. (2015). Sidetracked by trolleys: Why sacrificial moral dilemmas tell us little (or nothing) about utilitarian judgment. Social Neuroscience, 10(5), 551–560.

    Article  Google Scholar 

  • Kahane, G., Everett, J. A., Earp, B. D., Farias, M., & Savulescu, J. (2015). “Utilitarian” judgments in sacrificial moral dilemmas do not reflect impartial concern for the greater good. Cognition, 134, 193–209.

    Article  Google Scholar 

  • Kendler, K. S., & Gardner, C. O. (1998). Twin studies of adult psychiatric and substance dependence disorders: Are they biased by differences in the environmental experiences of monozygotic and dizygotic twins in childhood and adolescence? Psychological Medicine, 28(3), 625–633.

    Article  Google Scholar 

  • Knafo-Noam, A., Uzefovsky, F., Israel, S., Davidov, M., & Zahn-Waxler, C. (2015). The prosocial personality and its facets: Genetic and environmental architecture of mother-reported behavior of 7-year-old twins. Frontiers in Psychology, 6, 112.

    Article  Google Scholar 

  • Knopik, V. S., Neiderheiser, J., DeFries, J. C., & Plomin, R. (2017). Behavioral genetics (7th ed.). New York: Worth.

    Google Scholar 

  • Larsson, H., Andershed, H., & Lichtenstein, P. (2006). A genetic factor explains most of the variation in the psychopathic personality. Journal of Abnormal Psychology, 115(2), 221–230.

    Article  Google Scholar 

  • Mather, K., & Jinks, J. L. (1971). Biometrical genetics: The study of continuous variation (2nd rev. ed.). Ithaca: Cornell University Press.

  • McDonald, M. M., Defever, A. M., & Navarrete, C. D. (2017). Killing for the greater good: Action aversion and the emotional inhibition of harm in moral dilemmas. Evolution and Human Behavior, 38(6), 770–778.

    Article  Google Scholar 

  • Mitchell, K. S., Mazzeo, S. E., Bulik, C. M., Aggen, S. H., Kendler, K. S., & Neale, M. C. (2007). An investigation of a measure of twins’ equal environments. Twin Research and Human Genetics, 10(6), 840–847.

    Article  Google Scholar 

  • Mrazek, A. J., Chiao, J. Y., Blizinsky, K. D., Lun, J., & Gelfand, M. J. (2013). The role of culture–gene coevolution in morality judgment: Examining the interplay between tightness–looseness and allelic variation of the serotonin transporter gene. Culture and Brain, 1(2–4), 100–117.

    Article  Google Scholar 

  • Neale, M. C., & Cardon, L. R. (1992). Methodology for genetic studies of twins and families. Dordrecht: Kluwer Academic.

    Book  Google Scholar 

  • Neale, M. C., Boker, S. M., Xie, G., & Maes, H. H. (2003). Mx: Statistical modeling (6th ed.). Richmond.

  • Polderman, T. J., Benyamin, B., De Leeuw, C. A., Sullivan, P. F., Van Bochoven, A., Visscher, P. M., et al. (2015). Meta-analysis of the heritability of human traits based on fifty years of twin studies. Nature Genetics, 47(7), 702–709.

    Article  Google Scholar 

  • Ramos, A., Griffin, A., Neiderhiser, J., & Reiss, D. (2017). Did I inherit my moral compass? Behavior Genetics, 47, 672–673.

    Google Scholar 

  • Rushton, J. P. (2004). Genetic and environmental contributions to pro-social attitudes: A twin study of social responsibility. Proceedings of the Royal Society of London, B: Biological Sciences, 271(1557), 2583–2585.

    Article  Google Scholar 

  • Shenhav, A., Rand, D., & Greene, J. D. (2016). The relationship between intertemporal choice and following the path of least resistance across choices, preferences, and beliefs. Judgment and Decision Making, 12(1), 1–18.

  • Smith, K., Alford, J. R., Hibbing, J. R., Martin, N. G., & Hatemi, P. K. (2017). Intuitive ethics and political orientations: Testing moral foundations as a theory of political ideology. American Journal of Politcal Science, 61(2), 424–437.

    Article  Google Scholar 

  • Spencer, H. (1892). Social statics. London: Williams and Norgate.

    Google Scholar 

  • Stanovich, K. E. (1999). Who is rational? Studies of individual differences in reasoning. Psychology Press.

  • Suhler, C. L., & Churchland, P. (2011). Can innate, modular “foundations” explain morality? Challenges for Haidt's moral foundations theory. Journal of Cognitive Neuroscience, 23(9), 2103–2116.

    Article  Google Scholar 

  • Thomson, J. J. (1976). Killing, letting die, and the trolley problem. The Monist, 59(2), 204–217.

    Article  Google Scholar 

  • Tornero, E., Sánchez-Romera, J. F., Morosoli, J. J., Vázquez, A., Gómez, Á., & Ordoñana, J. R. (2018). Altruistic behavior among twins. Human Nature, 29(1), 1–12.

    Article  Google Scholar 

  • Tybur, J. M., Lieberman, D., & Griskevicius, V. (2009). Microbes, mating, and morality: Individual differences in three functional domains of disgust. Journal of Personality and Social Psychology, 97(1), 103–122.

    Article  Google Scholar 

  • Wilson, E. O. (1998). The biological basis of morality. The Atlantic Monthly, 281(4), 53–70.

    Google Scholar 

  • Wright, M. J., & Martin, N. G. (2004). Brisbane adolescent twin study: Outline of study methods and research projects. Australian Journal of Psychology, 56(2), 65–78.

    Article  Google Scholar 

  • Zak, P. J. (2013). The moral molecule: The new science of what makes us good or evil. Random House.

Download references

Acknowledgments

We thank Soad Hancock and Anjali Henders for project coordination, and David Smyth for database management. We thank John Hibbing, John Alford, and Nicholas Martin for their assistance in protocol development and data collection. Most of all, we thank the twins and their family members for participation in the study.

Funding

This work was supported by the US National Science Foundation (0729493,0721707).

Author information

Authors and Affiliations

  1. University of Nebraska, 509 Oldfather Hall, Lincoln, NE, 68588, USA

    Kevin Smith

  2. Pennsylvania State University, 307 Pond Lab, University Park, PA, 16802, USA

    Peter K. Hatemi

Authors
  1. Kevin Smith
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Peter K. Hatemi
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Peter K. Hatemi.

Ethics declarations

Conflicts of Interest/Competing Interests

Not applicable.

Ethics Approval

Data collection and analysis was approved and conducted within the guidelines set forth by the Queensland Institute of Medical Research human research ethics committee and with the Helsinki Declaration of 1975, as revised in 2008.

Consent to Participate

Informed consent was obtained from all participants before data collection.

Code Availability

Analyses were conducted in the free package Mx and in SAS 9.4.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

ESM 1

(PDF 441 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Smith, K., Hatemi, P.K. Are Moral Intuitions Heritable?. Hum Nat 31, 406–420 (2020). https://doi.org/10.1007/s12110-020-09380-7

Download citation

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12110-020-09380-7

Keywords

Search

Navigation