What Shapes Beliefs

Factual claims are increasingly disputed along political lines. For example, during the coronavirus pandemic, Republicans and Democrats in the US assessed the risks very differently. How does this type of polarization about facts arise?

Based on a pre-registered online experiment with nearly 1,900 participants in the US, the researchers Kai Barron, research fellow at the WZB, Anna Becker, assistant professor at Stockholm University, and Steffen Huck, research professor at the WZB, show that values shape beliefs: people’s views about how the world should be influence what they believe about how the world is. Values, in turn, are strongly linked to political affiliation. The study examines six contentious domains: migration, animal welfare, gender equality, abortion, prostitution, and same-sex marriage.

The findings provide direct evidence of politically motivated reasoning: when values are made salient, factual beliefs become more closely aligned with partisan positions. Importantly, financial incentives did not shift beliefs, suggesting that deep-seated values are a stronger motivating force than monetary considerations.

23/9/2025 kes