The United States' deep political divide has permeated every facet of U.S. social life. Whether revealed in a post on social media, a short video on TikTok, or the latest piece of news on Fox or NBC, it is hard to ignore political divisions in the U.S. This increasing polarization has inspired increased scientific attention to its antecedents and consequences. We wondered whether scientists themselves could be contributing to the ever-increasing tensions between the two major political parties in the U.S.

Researchers Contribute to Partisan Hostility

How could social scientists, and social psychologists specifically, contribute to this partisan hostility? One possibility is that polarization is exacerbated simply by the topics researchers choose to study. Most psychological research highlights differences among individuals and groups. This typical approach has shed light on a variety of both individual and collective level phenomena.

The pressure to publish peer-reviewed articles in academic journals (otherwise called "publish or perish") further encourages the search for significant group differences. Journals tend to be more interested in publishing articles about significant differences, rather than similarities, or the absence of differences. 

What if instead of focusing on differences between political groups, researchers instead asked questions about similarities? Would a focus on similarity lessen partisan hostility?

Research spearheaded by Hanel and colleagues emphasized the importance of studying and highlighting similarities between groups. It is not difficult to understand why this would be beneficial. We tend to like people and groups who we think are similar to us, after all.

Considering this idea, we examined whether Republicans and Democrats share similar attitudes, and if emphasizing those similarities could help reduce hostility between them.

When Political Similarities Are Accentuated Between Groups, Does That Foster Hostility Reduction?

We first conducted a survey of over 2,400 Republicans and Democrats in the lead-up to the 2020 presidential elections. We included questions about each person's moral and sociopolitical attitudes and beliefs.

Contrary to assumptions that Republicans and Democrats disagree about nearly everything, we found considerable similarity in their moral and political attitudes. At least 75% of responses overlapped. Both groups endorsed the importance of considering how fair or harmful their actions are for others, and they both believed that upholding democracy and finding bipartisan solutions is important for the U.S.

In a series of subsequent experiments involving more than 4,400 participants, we presented our findings to people who had not participated in the survey. Participants all saw the same findings, but they were randomly assigned to see the information described in different ways.  For some participants, our results were described as showing small differences between Democrats and Republicans, whereas for others they were described as showing a high degree of similarity between the two groups.

Results of these experiments consistently revealed that describing our findings as showing similarities rather than differences had interesting and important effects.  When findings were described as showing similarities, participants thought that their political opponents had attitudes and beliefs that were more similar to their own group.  They were more willing to find common ground with their political opponents on major social issues like gun control and abortion.  They expressed warmer feelings about their political opponents.  Finally, they were more likely to think that the self-concepts of people in their group overlapped with the self-concepts of people in the other group.

These results are important for two reasons. First, they highlight that focusing on group differences might inadvertently contribute to political tension. Second, when differences between groups are small, or similarities between groups are large, researchers should communicate their findings to the public.

Ultimately, these findings also are a timely reminder that, despite our differences, we share a lot of similarities in our beliefs, and that thinking about these similarities could help bridge the political divide present today.

For Further Reading

Syropoulos, S., & Leidner, B. (2023). Emphasizing similarities between politically opposed groups and their influence in perceptions of the political opposition: Evidence from five experiments. Personality and Social Psychology Bulletin, 0(0). >

Hanel, P. H. P., Maio, G. R., & Manstead, A. S. R. (2019). A new way to look at the data: Similarities between groups of people are large and important. Journal of Personality and Social Psychology, 116(4), 541–562.

Hanel, P. H. P., & Wolf, L. J. (2019). Leavers and Remainers after the Brexit referendum: More united than divided after all? British Journal of Social Psychology, 59(2), 470-493.

Hartman, R., Blakey, W., Womick, J. et al. (2022) Interventions to reduce partisan animosity. Nature Human Behaviour, 6, 1194–1205.

Stylianos Syropoulos is a Postdoctoral Research Fellow in the Department of Psychology and Neuroscience and the Schiller Institute for Integrated Science and Society at Boston College. He conducts research on moral, environmental, and conflict-related decision-making. His work examines why and when we choose to act prosocially and proenvironmentally, even if that might come at a personal cost.

Bernhard Leidner was a Full Professor of Psychology at the Department of Psychological and Brain Sciences at the University of Massachusetts Amherst. He studied the antecedents, consequences of international justice, intergroup violence, and collective action, as well as interventions to resolve conflict.