Assessment Sensitivity:
Making Sense of Relative Truth

John MacFarlane

Context and Content Lectures, Paris, 2010


My topic in these lectures is assessment sensitivity, a special kind of contextual sensitivity that I believe characterizes our thought and talk about what is tasty, what might be the case, what will be the case, what is known, and what ought to be done. Whereas ordinary contextual sensitivity (or “use sensitivity”) is the dependence of the truth of a sentence (or the accuracy of an assertion or belief) on features of the context in which it is used, assessment sensitivity is the dependence of the truth of a use of a sentence (or the accuracy of an assertion or belief) on features of the context in which it is assessed. Since a given speech act or belief can be assessed from indefinitely many contexts, none of which is privileged, a commitment to assessment sensitivity is a commitment to a certain kind of relativism about truth. Hence, in elaborating a semantic framework that allows for assessment sensitivity, we will need to “make sense of relative truth” and ward off the many objections that have been leveled against it. These foundational issues will be our primary concern in the lectures, which should be of interest both to philosophers and to linguists.

Abstracts of individual lectures follow.

Lecture 1. Motivating Relativism

We begin by examining three approaches to understanding the meaning of “tasty”: objectivism, contextualism, and expressivism. Each approach, we argue, is motivated by a genuine insight. The objectivist’s insight is that there can be real disagreement about what is “tasty.” The contextualist’s insight is that “tasty” is context-sensitive in some way. And the expressivist’s insight is that we can best undertand “tasty” by looking at what one does in characterizing something as “tasty.” The problem for these standard views is that each of them achieves its insight in a one-sided way — a way that loses the insights of the others. A relativist account — on which “tasty” expresses a property whose extension is relative to judges or their tastes — promises to do better. However, this kind of account involves us in a kind of relativism about truth that has widely been thought incoherent.

Lecture 1 Slides

Lecture 2. The Standard Objections

Why is relativism about truth so widely reviled in analytic circles? In this lecture, we consider some standard objections. It has been argued that the relativist has no coherent account of the bearers of relative truth values; that relativism about truth is self-refuting; that relativism about truth requires giving up the “Equivalence Schema” (according to which the proposition that p is true just in case p); and that the relativist has given no good account of the meaning of the relativized truth predicate. We extract from these standard objections some key problems that will be addressed in the remaining lectures.

Lecture 2 Slides

Lecture 3. Assessment Sensitivity

Most of the literature on truth relativism concerns either motivations for relativizing truth or arguments against the coherence of truth relativism. Comparatively little attention has been given to saying with precision what it is to be a truth relativist. In this lecture, we argue that relativism about truth should be understood as the view that truth is assessment-sensitive. Assessment sensitivity is understood by analogy with ordinary context sensitivity, or, as it is called here, use-sensitivity. Just as the truth of uses of ordinary context-sensitive sentences depends on features of the context in which they are used, so the truth of uses of assessment-sensitive sentences depends on features of the context in which they are assessed. Building on ideas of Lewis and Kaplan, we develop a framework that makes room for assessment-sensitivity.

Lecture 3 Slides

Lecture 4. Propositions

In this lecture, we consider how propositions can fit into a relativist semantic framework, and extend the notion of assessment sensitivity from sentences to propositions. This allows us to draw an important distinction between relativism about truth (which involves a commitment to assessment sensitivity) and nonindexical contextualism (which does not), and shows that taking propositional truth to be relative to parameters besides possible worlds (and possibly times) is neither necessary nor sufficient for relativism about truth, in the sense articulated here.

Lecture 4 Slides

Lecture 5. Making Sense of Relative Truth

A substantive philosophical question remains: what does it mean to talk of truth relative to a context of assessment? We seek to answer this question by explaining the theoretical role of assessment-relative truth in a truth-conditional semantic theory. The combined theory of lectures 3–5 allows us to formulate “relativist” semantic theories and derive from them substantive predictions about language use, so that they can be compared and evaluated against non-relativist alternatives. By doing this, I will suggest, we have “made sense of relative truth” and warded off apriori objections to its intelligibility.

Lecture 5 Slides

Lecture 6. Disagreement

Disagreement is a central crux in the debate between relativists, indexical and nonindexical contextualists, expressivists, and objectivists. In this lecture, we distinguish several varieties or “levels” of disagreement and show how the issue between the different semantic approaches we have considered can be reduced to an issue about what kind of disagreement there is in the domain under discussion.

Lecture 6 Slides