Lecture 6 — Disagreement

John MacFarlane (jgm@berkeley.edu)

Context and Content Lectures, Paris, 2010

The problem

Disagreement is at the crux of debates between contextualists (including nonindexical contextualists) and relativists. Contextualist accounts are criticized for failing to vindicate the sense that the parties in disputes of taste (etc.) disagree.

Frege’s view

…if something were true only for him who held it to be true, there would be no contradiction between the opinions of different people. So to be consistent, any person holding this view would have no right whatever to contradict the opposite view, he would have to espouse the principle: non disputandum est. He would not be able to assert anything at all in the normal sense, and even if his utterances had the form of assertions, they would only have the status of interjections—of expressions of mental states or processes, between which and such states or processes in another person there could be no contradiction.

Our task

Get clearer about what disagreement amounts to, and how it bears on the issues about truth and content that divide contextualists and relativists.

The wrong question?

The question

What is “real” or “genuine” disagreement?

is unfair to both sides:

Better questions

So instead let us ask:

State sense vs. activity sense

Having a disagrement vs. being in disagreement

Questions of form

What is the logical form of the relation we seek to explicate?

  1. x disagrees with y.
  2. x disagrees with y about whether p.
  3. x disagrees with y’s φing-in-context-c, where φ can be replaced by a verb phrase describing an attitude—for example, believe that Mary is smart, or hate the taste of grape jelly.



x disagrees with y’s φing in context c iff x could not coherently φ without change of mind—that is, without dropping some of her current attitudes.

where φing is a doxastic attitude
where φing is a nondoxastic attitude

Kölbel on disagreement

Two parties disagree if “neither could rationally come to believe what the other asserted without changing their mind.”

Simple example

George’s attitudes are not cotenable with Sally’s belief, because if George came to believe that McGovern is poor while still holding his other attitudes, his beliefs would be logically incoherent.

The Simple View

Simple view of disagreement
To disagree with someone’s belief that p is to have beliefs whose contents are jointly incompatible with p.

Special case of doxastic noncotenability (where attitudes limited to full belief).

Ned and Ted

cf. the atheist and the agnostic


Bob: The hypothesis is false.
Carol: I disagree, we need to do further testing.

What Bob has said is not incompatible with anything Carol believes. But, in asserting that the hypothesis is false, Bob has expressed a high degree of confidence that it is false. This confidence is not cotenable with Carol’s attitudes, which warrant a lower degree of confidence pending further tests.

Practical noncotenability

Too thin?

Disagreement in attitude

This occurs when Mr. A has a favorable attitude to something, when Mr. B has an unfavorable or less favorable attitude to it, and when neither is content to let the other’s attitude remain unchanged.

The difference between the two senses of “disagreement” is essentially this: the first involves an opposition of beliefs, both of which cannot be true, and the second involves an opposition of attitudes, both of which cannot be satisfied.

— C.L. Stevenson

Preclusion of joint satisfaction

Preclusion of joint satisfaction
x disagrees with y’s φing in context c iff the satisfaction of y’s φing in c would preclude the satisfaction of x’s (nondoxastic) attitudes.

Distinct from practical noncotenability

Whether preclusion of joint satisfaction obtains depends not just on the forces and contents of the relevant attitudes, but on the contexts in which they occur (who has them and when).

  1. There is a cupcake on the table. Alvin and Melvin both want to eat it. They both have a desire with the content to eat that cupcake. [cotenable attitudes, cannot both be satisfied]

  2. Meg and Peg are also looking at the cupcake. Meg desires to eat the frosting only. Peg desires to eat the cake part only. [noncotenable attitudes, can both be satisfied]


These examples assume that the contents of desires are properties or centered propositions, as seems reasonable given that they are expressed with infinitival clauses (to eat the cupcake).

If you think the contents of desires are standard possible-worlds propositions, then you can still distinguish between practical noncotenability and preclusion of joint satisfaction, but the distinction will be merely notional.

Preclusion of joint accuracy

Preclusion of joint accuracy

x disagrees with y’s φing in context c iff the accuracy of y’s φing in c would preclude the accuracy of x’s (doxastic) attitudes.


A belief/assertion that p in c is accurate [as assessed from cʹ] iff p is true as used at c [and assessed from cʹ].

Centered propositions

Centered propositions
A centered proposition has truth values relative to a world, time, and individual.

The centered proposition I am eating a sandwich is true at a world/time/individual triple  < w, t, i >  iff i is eating a sandwich at t in w.

Distinct from doxastic noncotenability

  1. Andy believes the centered proposition I am eating a sandwich, and David believes its complement, I am not eating a sandwich. [doxastically noncotenable, but joint accuracy is not precluded]

  2. At 1400h Andy believes the centered proposition I am eating a sandwich, and at 1500h David believes the centered proposition Nobody was eating a sandwich an hour ago. [doxastically cotenable, but joint accuracy is precluded]

Disagreement and accuracy


It is tempting to give a modal analysis of preclusion:

The accuracy of A precludes the accuracy of B iff it is impossible for B to be accurate if A is.

But this won’t work, since it might be impossible for B to be accurate, quite independently of A.

I rely on an intuitive grasp on preclusion.

The Simple View again

Simple view of disagreement

To disagree with someone’s belief that p is to have beliefs whose contents are jointly incompatible with p.


If two contents are incompatible, then there is no circumstance of evaluation e at which both are true.

Example #1 above shows that the Simple View is inadequate.

Cappelen and Hawthorne’s argument

You might use the Simple View as a premise in an argument against centered contents:

  1. Suppose that centered propositions can be the contents of beliefs.
  2. Two parties disagree if there is a proposition that one accepts and the other rejects.
  3. So it should follow that if Andy accepts I am eating a sandwich and David rejects I am eating a sandwich, they disagree.
  4. But this pattern of attitudes does not constitute disagreement.
  5. So, by reductio, centered propositions cannot be the contents of beliefs.

This is question-begging.

Cross-world disagreement?

Moreover, we can (perhaps) make the distinction even with regular possible-worlds propositions.

Objectivism, nonindexical contextualism, relativism

Before we continue, let’s briefly review the positions we distinguished in Lecture 4.

Preclusion and assessment sensitivity

Once we relativize accuracy, there are two interestingly different things we can mean by “preclusion of joint accuracy”:

Preclusion of joint accuracy

The accuracy of my attitudes (as assessed from any context) precludes the accuracy of your attitude or speech act (as assessed from that same context).

Preclusion of joint reflexive accuracy

The accuracy of my attitudes (as asesssed from my context) precludes the accuracy of your attitude or speech act (as assessed from your context).

Preclusion of joint reflexive accuracy

Disputes of taste

Instead of asking whether there is “genuine” disagreement in disputes of taste, and whether relativist views can account for “genuine” disagreement, let us ask:

Our example

Eduardo: Dulce de leche is tasty!

John: No, it’s not tasty.

Practical non-cotenability

We certainly seem to have this. Eduardo likes DDL, and I can’t come to have this attitude without a change in my own attitudes (in what I like).

C.L. Stevenson’s point: Even this is enough to explain much of the argumentation that arises in such disputes. Eduardo might have reason to change my attitude, and to do this he might call my attention to various salient facts about DDL, in an effort to induce a change in my taste. I might reply by noting other facts…

Practical non-cotenability

If this is all the disagreement there is, then even indexical contextualists can account for it.

Eduardo: I like dulce de leche!

John: I don’t like it.

Doxastic non-cotenability

Evidence for doxastic non-cotenability:

Can indexical contextualism account for this?

Lopez de Sa suggests: in cases like this, the parties are presupposing that they have relevantly similar tastes.

I think that what Eduardo has asserted — roughly, that he likes DDL — is false, because it conflicts with two of my beliefs: (a) that I don’t like DDL, and (b) that we have relevantly similar tastes.

Retreat to nonindexical contextualism

Can we stop here?

Is doxastic noncotenability enough?


Can we stop here?

Summing up

Type of accountPNCDNCPJAPJRA
indexical contextualismc
nonindexical contextualismcc

Faultless disagreement

A faultless disagreement is a situation where there is a thinker A, a thinker B, and a proposition (content of judgement) p, such that:



Faultless disagreement

faultless (w = epistemically warranted, t = true, a = accurate, n = not in violation of norms for assertion)

disagreement (n = doxastic non-cotenability, p = preclusion of joint accuracy)

Faultless disagreement

What might be meant by “the possibility of faultless disagreement”?

  1. The possibility that two parties might hold contradictory views about what is tasty while both believing what is true. (incoherent - this is how antirelativists often interpret the idea)

  2. The possibility that both parties in a dispute of taste can be warranted in holding the views they do, given the basis on which they hold them.

  1. The possibility that two parties who hold contradictory views about what is tasty might both be “getting it right,” in the sense of having accurate beliefs. (supports NIC, doxastic noncotenability)

  2. The possibility that two parties whose tastiness beliefs preclude each others’ accuracy are both succeeding in living up to the norms governing formation and retention of beliefs. (supports relativism, preclusion of joint accuracy)