Public Announcements, Public Lies and Recoveries

Area of Science:

• Epistemology
• Formal Logic
• Social Epistemology

Background:

• Public lying can engender false beliefs within a population.
• Understanding the dynamics of deception and belief formation is crucial in social epistemology.
• Existing models may not fully capture the impact of public announcements on collective beliefs.

Purpose of the Study:

• To provide a formal analysis of public lying and its relationship with public announcements.
• To investigate the process of recovery from false beliefs induced by public lies.
• To model different types of public lies and their effects on agents' convictions.

Main Methods:

• Utilizes KD45 models and conditional neighbourhood models for formal analysis.
• Introduces and analyzes update procedures within these logical frameworks.
• Develops and proves completeness for several reasoning systems, including public lies logic and lying and recovery logic.

Main Results:

• Distinguishes between simple lying updates (immune to convictions) and two-step lies (can shatter convictions).
• Demonstrates that negating a public lie does not automatically undo audience acceptance.
• Proposes a recovery process effective for factual beliefs but not for beliefs about beliefs.

Conclusions:

• Public lying, particularly two-step lying, poses a significant challenge to established beliefs.
• Effective recovery from public deception requires more than simple negation, especially concerning meta-beliefs.
• The formal framework provides tools for analyzing complex epistemic dynamics in the presence of public misinformation.