Epistemology of Disagreement

When someone you regard as an epistemic equal looks at the same evidence and reaches the opposite conclusion, how should you respond — by holding firm, by giving way, or by splitting the difference? The epistemology of disagreement studies the rational response to such conflict.

Definition

The epistemology of disagreement is the study of how the discovery that others disagree with one's belief — particularly disagreement with recognised epistemic peers — bears on the rationality of continuing to hold that belief.

Scope

This topic covers the epistemic significance of disagreement, centred on the case of epistemic peers — people roughly equal in evidence and competence. It examines the conciliationist view that one should reduce confidence in the face of peer disagreement, the steadfast view that one may retain one's belief, and intermediate positions such as the total-evidence view. It also touches on self-undermining worries and the bearing of disagreement on religion, politics, and philosophy. Broader social and institutional issues are treated in the parent area.

Core questions

• What is an epistemic peer, and when does peer disagreement arise?
• Should learning that a peer disagrees lower one's confidence?
• May one rationally remain steadfast on the grounds of one's own reasoning?
• Does conciliationism undermine itself, given disagreement about disagreement?

Key theories

Conciliationism

On the conciliationist view, defended by Christensen and Feldman, discovering that an epistemic peer disagrees gives one reason to reduce confidence in one's belief, often toward a middle position, since one cannot simply assume one's own assessment is the correct one.

The steadfast and total-evidence views

Kelly argues against pure conciliationism that the first-order evidence retains its weight, so a party who has in fact reasoned correctly may remain steadfast; the rational response depends on the total evidence, not on peerhood alone.

History

The problem was sharpened in the mid-2000s by Feldman, Christensen, and Kelly, who asked what rationality requires when recognised peers disagree on shared evidence. Conciliationist views, often modelled on the equal-weight treatment of conflicting instruments, were quickly opposed by steadfast and total-evidence positions, and the debate has since expanded to the significance of pervasive disagreement in philosophy, religion, and politics.

Debates

Conciliationism versus steadfastness

Conciliationists hold that peer disagreement should move one toward the other's view, but critics object that this gives too little weight to one's own reasoning and may be self-undermining, since the very thesis of conciliationism is itself disputed among peers.

Key figures

• David Christensen
• Thomas Kelly
• Richard Feldman

Seminal works

• christensen2007
• kelly2005

Frequently asked questions

What is an epistemic peer?

Roughly, an epistemic peer on some question is someone who is your equal with respect to the relevant evidence and to cognitive virtues such as intelligence, freedom from bias, and care, so that you have no antecedent reason to think you are more likely than they are to get the matter right.

Does conciliationism mean you must always give up your beliefs?

No. Conciliationism says peer disagreement gives some reason to reduce confidence, especially on the disputed question itself, but the degree depends on how genuine the peerhood is and on the rest of one's evidence. Steadfast and total-evidence theorists argue that one can sometimes rationally hold firm.