Seeing through opacity : a defense of the Russellian view of propositional attitudes

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Linguistics and Philosophy, 1994.Includes bibliographical references (v. 2, leaves 352-358).by Leonard Jay Clapp.Ph.D

On the metaphysics of belief

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Linguistics and Philosophy, 1998.Includes bibliographical references (leaves [119]-121).There is a traditional picture of belief, according to which someone's having a belief is that person's standing in a certain relation to an abstract object, a proposition. My dissertation examines the metaphysical demands that two problems for this picture of belief make on these abstract objects. The first problem comes to us from Frege's "On Sense and Reference," and the second concerns a certain sort of one's beliefs about oneself, which I call "indexical belief." Frege notes that someone can believe that Hesperus is Hesperus without believing that Hesperus is Phosphorus. It is a short step from Frege's observation to the claim that the sentence "A believes that Hesperus is Hesperus" could be true while "A believes that Hesperus is Phosphorus" is false. Quine has insisted that we cannot address this problem by taking either of these sentences to express a predication of the referent of both names, the planet Venus, as then both sentences would express the same predication of the same object, and this stands in evident tension with the fact that they can differ in truth value. In a recent response to Frege's problem, Mark Richard has taken exactly the route Quine has warned against. In my first chapter, I show that Richard's response is unsuccessful. I then consider the implications of the failure of his response on his proposed semantics for belief and the philosophical motivation he provides for it. I argue that his semantics for belief ascriptions stands in serious tension with its purported philosophical motivation. In the second and third chapters, I turn to the problem about indexical belief. The task of the second chapter is to identify this problem. To this end, I consider three of John Perry's arguments that the traditional picture of belief cannot accommodate indexical belief. I show that even if these arguments are sound, they give us no reason to think that the problem about indexical belief is in any way unique. I then suggest that there is a special problem about indexical belief, despite the failure of these three arguments to isolate it. Special difficulties attend an account of what it is to retain a tensed belief over time, and I suggest that the special problem about indexical belief is, in brief, a generalization of this problem about retention of tensed belief. In the third chapter, I raise the problem about indexical belief in a new way, as arising from a tension between several intuitively plausible claims about the relationship between beliefs and desires, on the one hand, and actions, on the other. This presentation of the problem brings out how the problem is special. I survey several solutions to this problem, including one due to Perry. I then argue that Perry's solution cannot characterize the specific kind of similarity between the beliefs of two different people who share an indexical belief. It allows too much to count as shared indexical belief. Thus Perry's solution inadequately addresses what I have suggested is the unique problem about indexical belief. Finally, I suggest that Frege's response to the problem I raise points the way towards an emendation of Perry's account that will enable it to suitably characterize the special way in which different people can share an indexical belief.by Cara Spencer.Ph.D

Representations of Mind

After defending the view that we can read off the metaphysics of the things we talk about from the form and interpretation of the language we use to talk about things, I develop and defend an account of the form and interpretation of propositional attitude reports (and some closely related constructions) and then read off the metaphysics of propositional attitudes. Views on the metaphysics of speech acts, propositions, and propositionally articulated thoughts also fall out of the account. The result is a tightly knit sets of views which I think together solve a number of outstanding philosophical problems. Given the centrality and importance of the attitudes and reports thereof to our making sense of ourselves and others as minded beings, not to mention their centrality to many domains of philosophy, the hope is that this makes a contribution to our self-understanding. It should also be a contribution to cognitive science

An Unexplored Aspect of Following a Rule

Though Wittgenstein has been most often identified as opposing Platonism in his writings about mathematics, I argue that Wittgenstein’s radical contextualism about mathematics finds its most natural opponent not in Platonism, but in a variety of formalism. One of Wittgenstein’s obvious formalist targets is his colleague the mathematician G. H. Hardy. If we discard this—still influential—picture of mathematics and replace it with a more nuanced account of mathematical activity as exemplified in the metamathematical thinking of the nineteenth century mathematician Augustus De Morgan, the example of the wayward pupil takes on a different significance. Against a more complex background, the wayward pupil can be reinterpreted as representing an exemplar of mathematical discovery. I consider the example of the nineteenth century engineer Oliver Heaviside whose unconventional approach in mathematics, driven by a need to efficiently elicit results from complex formulae for the purposes of aiding his research in electrical engineering, resulted in extraordinary mathematical advances. Yet, his approach to algebraic manipulation has the aspect of a wayward pupil. The wayward pupil, who may be making an error according to our ordinary criteria of rule-following, may be initiating new and fruitful paths. This possibility is largely unexamined in the larger discussion of Wittgenstein’s remarks on following a rule, and it explains Wittgenstein’s hesitation to label the wayward pupil’s actions straightforwardly incorrect

How we ascribe beliefs to others.

This thesis aims to provide a semantic account of belief ascriptions of the form 'A believes that S'. It begins with a detailed discussion of Saul Kripke's famous 'Puzzle about Belief, and tries to unearth a fundamental but rarely explicitly articulated assumption that gives the steps of the derivation of Kripke's Puzzle their intuitive plausibility. The assumption can be roughly stated as follows: belief ascriptions report on some single ontologically prior mental state which grounds the truth of a true ascription. A response to one form of Kripke's Puzzle is suggested at the end of this discussion. Several apparently diverse kinds of response to Kripke's Puzzle are critically evaluated and are found to be unsatisfactory. Many of the problems with these responses are traced to the fact that they are built upon the assumption that I suggest is at the heart of Kripke's Puzzle. The beginnings of a positive account of the semantics of belief ascriptions are given. The account gives a central role to the fact that the truth-value of a belief ascription depends on elements of the conversational setting in which it occurs. It is suggested that belief ascriptions are essentially answers to questions asked by an audience who has specific interests and makes specific assumptions about the agent and the setting of the ascription. The interests of the audience and the background assumptions that she makes are two- distinct sources of the context-sensitivity of belief ascriptions. The account makes no appeal to any kind of inner mental representations, but instead says that the truth of an ascription depends in a complex way on the agent's dispositions and capacities to do, say, think, and feel certain things. The thesis ends with a discussion of the de dicto/ de re distinction, and suggests that the distinction does not provide the most useful way of understanding belief ascription. It is argued that truly de re ascriptions are probably very rare, and that this does not therefore mean that most ascriptions are de dicto

Proof-theoretic Semantics for Intuitionistic Multiplicative Linear Logic

This work is the first exploration of proof-theoretic semantics for a substructural logic. It focuses on the base-extension semantics (B-eS) for intuitionistic multiplicative linear logic (IMLL). The starting point is a review of Sandqvist’s B-eS for intuitionistic propositional logic (IPL), for which we propose an alternative treatment of conjunction that takes the form of the generalized elimination rule for the connective. The resulting semantics is shown to be sound and complete. This motivates our main contribution, a B-eS for IMLL , in which the definitions of the logical constants all take the form of their elimination rule and for which soundness and completeness are established