The Frege-Geach Problem for Normative Propositions

Philosophy

Richard Anderson will be defending his PhD dissertation in the Philosophy Department.

Title:

The Frege–Geach Problem for Normative Propositions

Abstract:

The aim of this dissertation is to argue for the following claim: if Hanks' theory of propositions as act-types is correct, then there exists a plausible extension of this theory that solves the Frege–Geach problem for normative propositions—and, as a consequence, that solves the Frege–Geach problem for semantic expressivism more generally. In the dissertation I assume that Hanks' theory is correct, and in this framework develop an account of semantic expressivism that addresses three versions of the Frege–Geach problem: the embedding, inference and negation problems.

First, I examine in detail one extant attempt to support the claim, due to Hom and Schwartz. I argue that their extension is not plausible for two reasons: it does not satisfy a key expressivist constraint, and it encounters a problem with interrogatives. Then I argue that even if their extension were plausible, it would not solve the embedding problem for conditionals, for two reasons: it does not place suitable constraints on applications of force-indicators, and it encounters a problem with mixed descriptive–normative conditionals.

Second, I investigate the negation problem and use my results to argue in defense of a new extension of Hanks' theory that interprets normative predicates as having the dual semantic function of expressing both a set of admissible force-indicators and a deontic property. I argue that this extension is plausible, and then I further extend it by defining force-indicators that are generalizations of assertion and of normative endorsement (and of denial and anti-endorsement) and by defining logical connectives that apply uniformly to assertive and normative propositions. Finally, I argue that this extension provides a neutral semantic and logical framework that respects the semantic boundary between atomic descriptive and normative sentences, but that still addresses the Frege–Geach problem for normative propositions.