You can’t argue someone out of political polarization with facts because the way our brains process social info keeps us divided even when we’re trying to be rational.
April 10, 2026
Original Paper
Stable Polarisation despite Rational Communication: Recursive Social Learning with Diverse Priors
SSRN · 6440460
The Takeaway
We tend to blame echo chambers or fake news for our divided world. This model reveals that as long as we start with different core assumptions, talking to each other and updating our beliefs rationally will still lead us to permanently different conclusions.
From the abstract
The presumption that increased connectivity fosters consensus-often idealised as the 'wisdom of crowds'-sits uneasily with persistent social polarisation. Many explanations attribute this pattern to irrationality such as cognitive bias, motivated reasoning, or algorithmic amplification. We show instead that persistent disagreement can arise even under fully rational communication. In a computational multi-agent model of recursive Bayesian learning, agents treat others' opinions as endogenously g