Stephen Yablo

David Lewis asked in “A problem about permission” about the effects on context, specifically on the “sphere of permissibility,” of allowing behavior that had previously been forbidden. The framework of truthmaker semantics sheds useful light on this problem. Update procedures are definable in the truthmaker framework that capture more than Lewis was able to just with worlds. Connections are drawn with epistemic modals, belief revision and the semantics of exceptives. We consider how a truthmaker account of permissive update might be integrated into a larger semantic/pragmatic account of deontic language. Bridge principles are articulated associating types of deontic act with distinct update rules. Distinct forms of permission trigger distinct procedures because they aim at spheres more or less strongly verifying ◊φ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\Diamond \varphi $$\end{document}, the claim that φ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\varphi $$\end{document} is permissible.

Analytic semantics got its start when Frege pointed out differences in cognitive content between sentences that in some good sense “say the same.” Frege put cognitive content (in the form of sense) at the heart of semantic content. Most prefer nowadays to see cognitive contents as generated by semantic contents in context; a sentence's cognitive significance is an aspect rather of the information imparted by its use. I argue for a particular version of this idea. Semantic contents generate cognitive contents by operating levers in a larger piece of machinery, involving also the presupposition P one is leaning on and the subject matter M under discussion. A sentence's cognitive content is what its literal-content-restricted-to-P-worlds says about M. It's by triggering different presuppositions and/or different subject matters that coreferential names make their distinctive mark on a sentence's felt information value.

Holmes exists is false. How can this be, when there is no one for the sentence to misdescribe? Part of the answer is that a sentence’s topic depends on context. The king of France is bald, normally unevaluable, is false qua description of the bald people. Likewise Holmes exists is false qua description of the things that exist; it misdescribes those things as having Holmes among them. This does not explain, though, how Holmes does not exist differs in cognitive content from, say, Vulcan does not exist. Our answer builds on an observation of Kripke’s: even if Holmes exists, he is not in this room, for we were all born too late.

In his Meditations, René Descartes asks, "what am I?" His initial answer is "a man." But he soon discards it: "But what is a man? Shall I say 'a rational animal'? No: for then I should inquire what an animal is, what rationality is, and in this way one question would lead down the slope to harder ones." Instead of understanding what a man is, Descartes shifts to two new questions: "What is Mind?" and "What is Body?" These questions develop into Descartes's main philosophical preoccupation: the Mind-Body distinction. How can Mind and Body be independent entities, yet joined--essentially so--within a single human being? If Mind and Body are really distinct, are human beings merely a "construction"? On the other hand, if we respect the integrity of humans, are Mind and Body merely aspects of a human being and not subjects in and of themselves? For centuries, philosophers have considered this classic philosophical puzzle. Now, in this compact, engaging, and long-awaited work, UCLA philosopher Joseph Almog closely decodes the French philosopher's argument for distinguishing between the human mind and body while maintaining simultaneously their essential integration in a human being. He argues that Descartes constructed a solution whereby the trio of Human Mind, Body, and Being are essentially interdependent yet remain each a genuine individual subject. Almog's reading not only steers away from the most popular interpretations of Descartes, but also represents a scholar coming to grips directly with Descartes himself. In doing so, Almog creates a work that Cartesian scholars will value, and that will also prove indispensable to philosophers of language, ontology, and the metaphysics of mind.

Essentialists hold that certain of a thing's properties are specially fundamental, antiessentialists that all of a thing's properties are on a par. As a result, essentialists can explain how, e.g., a statue and its clay are different, but not how they are the same, whereas antiessentialists can explain how they're the same but not how they're different. Ordinarily, though, we reckon them in one sense the same and in another different. ;To accomodate the ordinary view, essentialism and antiessentialism must be brought together. To this end, I identify a property as categorical if its possession in a world speaks to what goes on in that world alone; count essentialist particulars contingently identical in a world if they share their categorical properties there; and introduce antiessentialist, or concrete, particulars as entities for which contingent identity is all the identity there is. Concrete particulars emerge as limiting cases of the essentialist particulars with which they were formerly contrasted, and essentialism and antiessentialism are to that extent reconciled. ;With matters so complicated clarity is at a premium, so the scheme is formalized. Each Kripke model of quantified modal logic is supplemented with a set of properties, constrained so that essences drawn from the set specify what a thing must be like to be the thing it is. When one thing's essence includes another's, they are variants. Properties insensitive to the difference between variants are categorical, and contingent identity is sameness of categorical properties. If concrete things are things existing in one world only, then all their properties are on a par, and they're contingently identical iff properly identical. To show the tractability of reasoning about particulars thus understood, I give a sound and complete logic. ;Formalism isn't an end in itself, but the present formalism pays its way by bringing new clarity to traditional issues: I prove that indiscernibles are identical; give an analysis of kind properties; establish the relativity of cross-world identity between concrete things to kinds; forge new links between modality, time, and potentiality; and give an improved counterfactual account of causation

Kripke, argued like this: it seems possible that E; the appearance can't be explained away as really pertaining to a "presentation" of E; so, pending a different explanation, it is possible that E. Textbook Kripkeans see in the contrast between E and its presentation intimations of a quite general distinction between two sorts of meaning. E's secondary or a posteriori meaning is the set of all worlds w which E, as employed here, truly describes. Its primary or a priori meaning is the set of all w such that if w is actual, then E is true. "Conceivability error" occurs when a primary possibility is mistaken for a secondary one. Textbook Kripkeanism is rejected on the grounds that it makes meaning too modal and modality too much a matter of meaning.

Mark Colyvan (2010) raises two problems for ‘easy road’ nominalism about mathematical objects. The first is that a theory’s mathematical commitments may run too deep to permit the extraction of nominalistic content. Taking the math out is, or could be, like taking the hobbits out of Lord of the Rings. I agree with the ‘could be’, but not (or not yet) the ‘is’. A notion of logical subtraction is developed that supports the possibility, questioned by Colyvan, of bracketing a theory’s mathematical aspects to obtain, as remainder, what it says ‘mathematics aside’. The other problem concerns explanation. Several grades of mathematical involvement in physical explanation are distinguished, by analogy with Quine’s three grades of modal involvement. The first two grades plausibly obtain, but they do not require mathematical objects. The third grade is likelier to require mathematical objects. But it is not clear from Colyvan’s example that the third grade really obtains