Overview

The epistemology of disagreement asks: What should I do when I discover that an “epistemic peer” (someone just as smart and well-informed as I am) disagrees with me? Should I stick to my guns or lower my confidence?

Core Idea

The core idea is that disagreement from a peer is a form of evidence—evidence that I might be wrong.

Formal Definition

Epistemic Peer Disagreement: A situation where two agents, S1 and S2, are roughly equal in intelligence, reasoning ability, and access to evidence, yet S1 believes P and S2 believes not-P.

Intuition

You and a friend calculate a tip at a restaurant. You get $20. Your friend gets $22. You are both good at math.

  • Conciliationist: “We should both suspend judgment and check again.” (Split the difference).
  • Steadfaster: “I did the math carefully. I see clearly that it’s $20. I’m sticking with it.”

Examples

  • Politics: Intelligent, informed people disagree about tax policy.
  • Religion: Intelligent, informed people disagree about the existence of God.
  • Philosophy: Philosophers disagree about almost everything!

Common Misconceptions

  • Misconception: If people disagree, there is no truth.
    • Correction: Disagreement is about justification, not truth. One person is right and the other is wrong (or both are wrong), but the question is what they should believe given the conflict.
  • Misconception: I can just assume the other person is biased.
    • Correction: If they are a true “peer,” you can’t assume that without independent evidence.
  • Conciliationism: The view that you should adjust your confidence (move toward the peer).
  • Steadfastness: The view that you can reasonably maintain your belief despite peer disagreement.
  • Uniqueness Thesis: The idea that a body of evidence justifies only one specific attitude (belief, disbelief, or suspension).

Applications

  • Civil Discourse: Understanding disagreement can promote intellectual humility and better dialogue.
  • Expert Consensus: When experts disagree (e.g., in climate science or economics), what should the layperson believe?

Criticism and Limitations

  • Spinelessness: If Conciliationism is true, we might end up suspending judgment on everything controversial (politics, religion, philosophy), leading to intellectual paralysis.
  • Self-Undermining: Does the Conciliationist have to suspend judgment about Conciliationism itself (since many philosophers disagree with it)?

Further Reading

  • Disagreement by Richard Feldman and Ted A. Warfield
  • The Epistemology of Disagreement: New Essays by David Christensen