The Conversational Role of Centered Contents

Abstract

Some philosophers, for example David Lewis, have argued for the need to introduce de se contents or centered contents, i.e. contents of thought and speech the correctness of believing which depends not only on the possible world one inhabits, but also on the location one occupies. Independently, philosophers like Robert Stalnaker (and also David Lewis) have developed the conversational score model of linguistic communication. This conversational model usually relies on a more standard conception of content according to which the correctness of believing a content depends merely on the possible world one occupies. The aim of this paper is to develop a modified conversational score model that operates with centered contents. I begin by explaining how in principle centered contents can figure in the transfer of information from one thinker to another. Here I distinguish the local portability approach from the portable surrogate approach. Then I explain how these modes of information transfer can be exploited in a stalnakerian conversational model involving centered contents, proposing a modified update rule for assertion. Preliminaries 1Semantic theories for natural languages usually employ some notion of semantic content. A semantics for a given language L will assign such contents to sentences at contexts of use. These assignments are supposed, via some further assumptions, to allow predictions as to the conditions under which the utterance of a sentence of L would be true, and derivatively predictions about logical truth and logical consequence (see e.g. Lewis 1970, p. 190; Kaplan 1977, p. 522;Predelli 2006; Stanley 2007, introduction;Partee 2010). Data concerning the truth conditions of (potential) utterances are assumed to be observable 2 independently and thereby to provide a method for empirically testing the semantics. The contents assigned to sentences in context are usually treated as multi-purpose representational contents, i.e. contents that can model representational aspects of linguistic utterances as well as of mental states, such as beliefs. Whether they are called "thoughts", "propositions", "contents" or whatever, the basic idea is the same: these entities represent the world in some way, and and certain utterances (e.g. assertions) or states (e.g. beliefs) with such an entity as content can be assessed as to their success in representing the world. This 1 Those already familiar with recent discussions of communication with centered contents, who are keen to cut straight to the issues, and who are not interested in preliminary or foundational questions, can safely skip this section. 2 Observation is a problematic notion, and it is no less problematic in this case. If, for example, we think of the predictions as concerning a shared language, then we might consult the judgements of competent users of that language as to the conditions under which it would be correct to use a sentence. Thus we would be operating on the assumption that there is a correlation between these users' judgements ...

The meaning of “I” in “I”‐thought

“…For instance, it may be construed as the hearer's self‐ascription of the property of being a subject such that one is addressed by someone who is about to be attacked by a bear (Weber, , p. 213, cf. Gibbard, ), or that of being a subject who inhabits a world where the latest contributor to the present conversation is about to be attacked by a bear (Kölbel, , p. 108). In any case, a difference in the properties self‐ascribed serves to explain the behavioural difference between the speaker and the hearer…”

De Se Assertion

“…The most straightforward way of extending Lewis's proposal regarding de se attitudes to assertion and communication is to say that although the content of Fenrong's belief in (1) is the property of being about to be attacked by a bear, the content of her assertion is a different one, namely, an "uncentered" one, such as the proposition that (at a certain time t) Fenrong is about to be attacked by a bear. The combination of a Lewisian theory of attitude content and a Kaplanian theory of discourse content, at least for sentences such as (1), has been the preferred option for many theorists, including Egan (2007Egan ( , 2012, Moss (2012) and Kölbel (2013). As Egan (2012: 576) puts it: "Given [a certain] acceptance conditions-based story about the theoretical role of content in an account of assertion and communication, we definitely do not want to go for a semantic theory that assigns de se content to indexical sentences.…”

“…Stephenson 2007, like Egan (2007Egan ( , 2012Egan ( , 2014, Kölbel (2013) or Moss (2013), works with a Stalnakerian model of assertion and communication (Stalnaker 1978, according to which the goal of assertion is to lead to an update of the common ground. For Stalnaker, the common ground is modeled as a set of possible worlds; namely, those that, given what has been accepted in the conversation, could turn out to be the actual world.…”

In Defense of De Se Content

“…Following Max Kölbel (), let us introduce the notion of a globally portable proposition as a proposition that does not vary in truth‐value within a world. Let us take locations as points of evaluation within a world.…”