When cardinals strategize: An agent-based model of influence and ideology for the papal conclave

2025-05-11

AI Summary

This study investigates how social influence, strategic voting, and ideological polarization affect the duration of papal conclaves. We propose a novel two-layer agent-based model incorporating an “effective voting” mechanism and bipolar ideological blocs to simulate the evolution of consensus among cardinals under dynamic preference updating, stochastic interactions, and strategic realignments. Numerical simulations and sensitivity analyses reveal that ideological polarization significantly increases the average number of voting rounds, whereas cross-bloc realignment capacity and informal pre-consensus formation critically accelerate convergence. The 2025 conclave’s unusually rapid outcome empirically validates the decisive role of informal coordination in resolving deadlock. By integrating micro-level behavioral mechanisms with macro-level institutional constraints, this work establishes a new computational paradigm for analyzing institutional decision-making dynamics within closed elite groups.

Technology Category

• Game Theory and Economic Paradigms: Social Choice / Voting
• Multiagent Systems: Mechanism Design
• Humans and AI: Voting

Application Category

• Social Networks and Social Media: Media and governance, opinion dynamics, filter bubbles, polarization
• User Modeling, Personalization and Recommendation: Studies of user behavior, including longitudinal effects of personalized systems
• Web Mining and Content Analysis: Models for Web evolution

Abstract

We propose and analyze two agent-based models to investigate the dynamics of papal conclaves, focusing on how social influence, strategic voting, and ideological alignment affect the time required to elect a pope. In the first model, cardinals interact through two mechanisms: with probability $p$, they imitate the choice of a randomly selected peer, and with probability $q$, they shift support to the most voted candidate from the previous round. Additionally, strategic behavior is introduced via ``useful voting'', where agents abandon their preferred candidate if he receives less than a certain fraction of the votes, switching instead to the most viable alternative. A candidate must secure a qualified majority of two-thirds to be elected. After that, we extend the framework by incorporating ideological blocs, assigning each cardinal and candidate to one of two groups (e.g., progressives and conservatives). Cardinals initially vote for candidates from their own group, but may cross ideological lines due to strategic considerations. We initialize the population with $20%$ conservative cardinals, reflecting the current composition shaped by papal appointments. Numerical simulations show that ideological polarization can delay the election, increasing the average number of voting rounds. Our results highlight the crucial role of both strategic flexibility and ideological structure in collective decision-making under conditions found in papal conclaves. The recent rapid outcome of the 2025 conclave, despite a polarized electorate, suggests that informal consensus-building - possibly prior to voting - may play a decisive role in accelerating convergence, complementing the mechanisms explored in our model.

Problem

• Investigates social influence and strategic voting in papal conclaves
• Examines ideological alignment's impact on election duration
• Analyzes consensus-building effects on conclave decision-making speed

Innovation

• Agent-based model with social influence and strategic voting
• Useful voting mechanism for candidate viability
• Incorporation of ideological blocs for polarization analysis