What assertion doesn't show

McHugh, Conor (2012) What assertion doesn't show. European Journal of Philosophy, 20, 407-429. (doi:10.1111/j.1468-0378.2010.00412.x).

Record type: Article

Abstract

Some recent arguments against the classical invariantist account of knowledge exploit the idea that there is a ‘knowledge norm’ for assertion. It is claimed that, given the existence of this norm, certain intuitions about assertability support contextualism, or contrastivism, over classical invariantism. In this paper I show that, even if we accept the existence of a knowledge norm, these assertability-based arguments fail. The classical invariantist can accommodate and explain the relevant intuitions about assertability, in a way that retains the idea that knowledge is the epistemic norm for assertion. When we consider the role of assertion as a conversational act, it becomes plausible that a subject's epistemic warrant to assert can be defeated even though she has knowledge. This defeasibility thesis is what allows the classical invariantist to accommodate and explain the kinds of intuitions on which assertability-based arguments depend.

Arguments from claims about assertability to claims about knowledge, or about ‘knowledge’, can be found in recent work by Keith DeRose (2002) and Jonathan Schaffer (2008). These arguments exploit the idea that knowledge is the epistemic standing required for epistemically warranted assertion. DeRose and Schaffer argue that, given the existence of this ‘knowledge norm’ for assertion, certain intuitions about assertability put pressure on the classical invariantist account of knowledge. They conclude that we should reject classical invariantism in favour of, respectively, contextualism and contrastivism.1 I am going to call these arguments ‘assertability-based arguments’.

One response to these arguments would be to challenge the existence of the supposed knowledge norm for assertion. I will show, however, that assertability-based arguments fail even if we accept that there is such a norm. The classical invariantist can accommodate and explain the relevant intuitions about assertability, in a way that retains the idea that knowledge is the epistemic standing required for epistemically warranted assertion.

This requires paying attention to the role of assertion as a conversational speech act. When we consider this role, I will argue, it becomes plausible that a subject's epistemic warrant to assert can be defeated even though she has knowledge. This defeasibility thesis is what allows the classical invariantist to accommodate and explain the kinds of intuitions on which assertability-based arguments depend.

In Section 1 I will introduce the knowledge norm for assertion and outline assertability-based arguments against classical invariantism. In Section 2 I will discuss the role of assertion in conversation in order to show that these assertability-based arguments fail. I will conclude that assertability doesn't show much about knowledge.

This record has no associated files available for download.