Online research in philosophy

Consider the following argument: All men are mortal; Socrates is a man; therefore, Socrates is mortal. Intuitively, what makes this a valid argument has nothing to do with Socrates, men, or mortality. Rather, each sentence in the argument exhibits a certain logical form, which, together with the forms of the other two, constitute a pattern that, of itself, guarantees the truth of the conclusion given the truth of the premises. More generally, then, the logical form of a sentence of natural language is what determines both its logical properties and its logical relations to other sentences. The logical form of a sentence of natural language is typically represented in a theory of logical form by a well-formed formula in a ‘logically pure’ language whose only meaningful symbols are expressions with fixed, distinctly logical meanings (e.g., quantifiers). Thus, the logical forms of the sentences in the above argument would be represented in a theory based on pure predicate logic by the formulas ‘∀x(Fx ⊃ Gx)’, ‘Fy’, and ‘Gy’, respectively, where ‘F’, ‘G’, and ‘y’ are all free variables. The argument’s intuitive validity is then explained in virtue of the fact that the logical forms of the premises formally entail the logical form of the conclusion. The primary goal of a theory of logical form is to explain as broad a range of such intuitive logical phenomena as possible in terms of the logical forms that it assigns to sentences of natural language.

Over the years, I’ve been asked many times what “logical form” is, as applied to natural language. This is a natural enough question to address to me; after all, I’ve written a book titled Logical Form, and I’ve been asked to write any number of papers on the topic. This question, it seems to me, is certainly a “big” question, and big questions deserve big answers. I must admit, however, to being somewhat baffled as to how to do this satisfactorily, since big answers to big questions unfortunately tend to the trivial. With a nod to Wittgenstein, logical form has always seemed to me to be something that you know it when you see it; it is clear enough when it pops up, but one is hard pressed to say just what it is, to define it. This is so even though the meanings of the words “logical” and “form” seem straightforward enough; what I find puzzling is how the first word is supposed to modify the second. What is it that makes a form logical, as opposed to something else that is not logical? This, it seems to me, is a very hard question to answer indeed, for if we cannot contrast logical form with some other type of form, then every form (or no form) is a logical form, and we have arrived at the triviality previously mentioned.

Carruthers’ argument depends on viewing logical form as a linguistic level. But logical form is typically viewed as underpinning general purpose inference, and hence as having no particular connection to language processing. If logical form is tied directly to language, two problems arise: a logical problem concerning language acquisition and the empirical problem that aphasics appear capable of cross-modular reasoning.

Some time ago, John Perry argued that the content of an indexical belief, that is, a belief expressible with a sentence containing an indexical or demonstrative, cannot be a proposition. I consider several of his arguments for this view, and show that they can be extended to show that belief expressible with other non-indexical expressions such as natural kind terms and proper names presents the very same problem for the traditional picture. I then suggest that if indexical belief has any special status, this is not because it has a special kind of content, but rather because action is impossible if agents do not have indexical belief.

Indexicals are linguistic expressions whose meaning remain stable while their reference shifts from utterance to utterance. Paradigmatic cases in English are ‘I’, ‘here’, and ‘now’. Recently, a number of authors have argued that various constructions in our language harbor hidden indexicals. We say 'hidden' because these indexicals are unpronounced, even though they are alleged to be real linguistic components. Constructions taken by some authors to be associated, or to ‘co-habit’, with hidden indexicals include: definite descriptions and quantifiers more generally (hidden indexical refers to a domain – Davies (1981), Westerstahl (1985), Soames (1986), Higginbotham (1988), Stanley and Williamson (1995)), propositional attitude verbs (hidden indexical refers to a mode of presentation – Richard (1990)), comparative adjectives (hidden indexical refers to comparison classes – Partee (1989), Kamp (1975), Ludlow (1989)). An interesting recent addition is the view that all nouns are associated with a hidden indexical referring to a domain restriction (Stanley and Szabo (2000), Stanley..

Contextualism concerning vagueness (hereafter ‘CV’) is a popular response to the puzzle of vagueness.[1] The goal in this paper is to uncover in what ways vagueness may be a particular species of context-sensitivity. The most promising form of CV turns out to be a version of socalled ‘Non-Indexical Contextualism’.[2] In §2, we sketch a generic form of CV (hereafter ‘GCV’). In §3, we distinguish between Truth CV and Content CV. A non-indexical form of CV is a form of Truth CV, while an indexical form of CV is a form of Content CV. In §4, we argue that the theory of vagueness given in Fara (2000) is crucially incomplete but is best seen as a non-indexical form of CV. In §5, we set forth four kinds of error-theory to which CV might be committed. It turns out that Non-Indexical CV is committed to a weaker, and more plausible, error-theory than Indexical CV. In §6, we address a challenge posed by Keefe (2007) to the effect that CV entails that any speech report of what has been said by a particular vague utterance, where the context of utterance and the reporting context are relevantly different, will almost always be inaccurate. While this challenge is prima facie effective against Indexical CV it proves to be less effective against Non-Indexical CV. In §7, we look at two tests for context-sensitivity and assess whether they can be employed against CV. These tests, if cogent, reveal that the only workable form of CV is Non-Indexical CV.

Indexicals are linguistic expressions whose meaning remain stable while their reference shifts from utterance to utterance. Paradigmatic cases in English are ‘I’, ‘here’, and ‘now’. Recently, a number of authors have argued that various constructions in our language harbor hidden indexicals. We say ’hidden’ because these indexicals are unpronounced, even though they are alleged to be real linguistic components. Constructions taken by some authors to be associated, or to ‘co-habit’, with hidden indexicals include: definite descriptions and quantifiers more generally (hidden indexical refers to a domain – Davies (1981), Westerstahl (1985), Soames (1986), Higginbotham (1988), Stanley and Williamson (1995)), propositional attitude verbs (hidden indexical refers to a mode of presentation – Richard (1990)), comparative adjectives (hidden indexical refers to comparison classes – Partee (1989), Kamp (1975), Ludlow (1989)). An interesting recent addition is the view that all nouns are associated with a hidden indexical referring to a domain restriction (Stanley and Szabo (2000), Stanley (2002)).

Simon Blackburn has shown that there is an analogy between the problem of moral motivation in ethics (how can moral reasons move us?) and the problem of what we might call the power of logical reasons (how can logical reasons move us, what is the force of the 'logical must?'). In this paper, I explore further the parallel between the internalism problem in ethics and the problem of the power of logical reasons, and defend a version of psychologism about reasons, although not one of the Humean form. I discuss two forms of cognitivism: (i) a pure cognitivism and 'hard' realism modelled after Dancy's parallel conception in ethics: when we grasp logical reasons we grasp facts, which are directly known to us; (ii) a Kantian form of cognitivism, based on the idea that compulsion by reason goes with the capacity of reflection. I argue that (i) is implausible, and that (ii) fails to meet the internalist requirement. One would then seem to be left with what Dancy calls, about practical reasoning, psychologism about reasons. I sketch what might be such a psychologism. But it fails to account for the objectivity of logical reasons. I argue that the relevant state here is a form of dispositional knowledge of logical reasons.