• How to Prove Hume's Law
    Journal of Philosophical Logic. forthcoming.
    This paper proves a precisification of Hume’s Law—the thesis that one cannot get an ought from an is—as an instance of a more general the- orem which establishes several other philosophically interesting, though less controversial, barriers to logical consequence.
  •  371
    Logical nihilism: Could there be no logic?
    Philosophical Issues 28 (1): 308-324. 2018.
    Logical monists and pluralists disagree about how many correct logics there are; the monists say there is just one, the pluralists that there are more. Could it turn out that both are wrong, and that there is no logic at all?
  •  99
    Logical pluralism is the view that there is more than one logic. Logical normativism is the view that logic is normative. These positions have often been assumed to go hand-in-hand, but we show that one can be a logical pluralist without being a logical normativist. We begin by arguing directly against logical normativism. Then we reformulate one popular version of pluralism—due to Beall and Restall—to avoid a normativist commitment. We give three non-normativist pluralist views, the most promis…Read more
  •  26
    This paper looks at what David Kaplan's work on indexicals can teach us about logic and the philosophy of logic, and also what Kaplan's logic (i.e. the Logic of Demonstratives) can teach us about indexicals. The lessons are i) that logical consequence is not necessary truth-preservation, ii) that that the linguistic doctrine of necessary truth (also called conventionalism about modality) fails, and iii) that there is a kind of barrier to entailment between non-context-sensitive and context-sens…Read more
  •  98
    Deviance and Vice: Strength as a Theoretical Virtue in the Epistemology of Logic
    Philosophy and Phenomenological Research 99 (3): 548-563. 2019.
    This paper is about the putative theoretical virtue of strength, as it might be used in abductive arguments to the correct logic in the epistemology of logic. It argues for three theses. The first is that the well-defined property of logical strength is neither a virtue nor a vice, so that logically weaker theories are not—all other things being equal—worse or better theories than logically stronger ones. The second thesis is that logical strength does not entail the looser characteristic of sci…Read more
  •  319
    Logic isn’t normative
    Inquiry: An Interdisciplinary Journal of Philosophy 1 1-18. forthcoming.
    Some writers object to logical pluralism on the grounds that logic is normative. The rough idea is that the relation of logical consequence has consequences for what we ought to think and h...
  •  101
    Indexicals and Sider's Neo-Linguistic Account of Necessity
    Res Philosophica 94 (3): 385-397. 2017.
    Sider offers a new take on a linguistic account of necessity. In this paper, I assess his view’s vulnerability to objections made against more traditional linguistic accounts, especially an argument I call the “indexical problem.” I conclude that the indexical problem has no force against Sider’s approach because the view is able to attribute modal properties directly to propositions, rather than indirectly via analytic sentences that express them. However, Sider also argues that traditional lin…Read more
  •  105
    The analytic/synthetic distinction looks simple. It is a distinction between two different kinds of sentence. Synthetic sentences are true in part because of the way the world is, and in part because of what they mean. Analytic sentences - like all bachelors are unmarried and triangles have three sides - are different. They are true in virtue of meaning, so no matter what the world is like, as long as the sentence means what it does, it will be true. -/- This distinction seems powerful bec…Read more
  •  252
    Knowledge by indifference
    with John Doris
    Australasian Journal of Philosophy 86 (3). 2008.
    Is it harder to acquire knowledge about things that really matter to us than it is to acquire knowledge about things we don't much care about? Jason Stanley 2005 argues that whether or not the relational predicate 'knows that' holds between an agent and a proposition can depend on the practical interests of the agent: the more it matters to a person whether p is the case, the more justification is required before she counts as knowing that p. The evidence for Stanley's thesis includes a number o…Read more
  •  153
    A new problem for the linguistic doctrine of necessary truth
    In Cory D. Wright & Nikolaj J. L. L. Pedersen (eds.), New Waves in Truth, Palgrave-macmillan. pp. 267--281. 2010.
    My target in this paper is a view that has sometimes been called the ‘ Linguistic Doctrine of Necessary Truth ’ and sometimes ‘Conventionalism about Necessity’. It is the view that necessity is grounded in the meanings of our expressions—meanings which are sometimes identified with the conventions governing those expressions—and that our knowledge of that necessity is based on our knowledge of those meanings or conventions. In its simplest form the view states that a truth, if it is necessary, i…Read more
  •  140
    Routledge Companion to Philosophy of Language (edited book)
    with Delia Graff Fara
    Routledge. 2012.
    Philosophy of language is the branch of philosophy that examines the nature of meaning, the relationship of language to reality, and the ways in which we use, learn, and understand language. _The Routledge Companion to Philosophy of Language _provides a comprehensive and up-to-date survey of the field, charting its key ideas and movements, and addressing contemporary research and enduring questions in the philosophy of language. Unique to this _Companion _is clear coverage of research from the r…Read more
  •  61
    Hybrid Identities and Just Being Yourself
    Inquiry: An Interdisciplinary Journal of Philosophy 57 (4): 455-465. 2014.
    This paper points out a tension between Agustín Rayo's criteria for singulartermhood and his explicit views on the status of Hybrid Identities, that is, identity statements that use singular terms from two different Systems of Representation, such as "7=Julius Caesar" or more suggestively "I am b" where "b" is a singular term referring to my brain. It argues that non-trivial Hybrid Identities are common and important in philosophy and elsewhere, and it suggests a friendly alternative that invol…Read more
  •  256
    The Justification of the Basic Laws of Logic
    Journal of Philosophical Logic 44 (6): 793-803. 2015.
    Take a correct sequent of formal logic, perhaps a simple logical truth, like the law of excluded middle, or something with premises, like disjunctive syllogism, but basically a claim of the form \.Γ can be empty. If you don’t like my examples, feel free to choose your own, everything I have to say should apply to those as well. Such a sequent attributes the properties of logical truth or logical consequence to a schematic sentence or argument. This paper aims to answer the question of how belief…Read more
  •  51
    Language, Locations and Presupposition
    Linguistic and Philosophical Investigations 9 194-205. 2010.
    Could it ever be right to say that a language---as opposed to a speaker of the language---makes, or presupposes or somehow commits itself to certain claims? Such as that certain kinds of objects exist, or that things are a certain way? It can be tempting to think not, to think that languages are just the neutral media through which speakers make claims. Yet certain, surprisingly diverse, phenomena---analyticity, racial epithets, object-involving direct reference, arithmetic, and semantic paradox…Read more
  •  137
    Barriers to Implication
    with Greg Restall
    In Charles Pigden (ed.), Hume on Is and Ought, Palgrave Macmillan. 2010.
    The formulation and proof of Hume’s Law and several related inference barrier theses.
  •  65
    Review: Warren Goldfarb’s Deductive Logic (review)
    Australasian Journal of Logic 3 63-66. 2005.
    Deductive Logic is an introductory textbook in formal logic. The book is divided into four parts covering (i) truth-functional logic, (ii) monadic quantifi- cation, (iii) polyadic quantification and (iv) names and identity, and there are exercises for all these topics at the end of the book. In the truth-functional logic part, the reader learns to produce paraphrases of English statements and arguments in logical notation (this subsection is called “analysis”), then about the semantic properties…Read more
  •  132
    This paper investigates, formulates and proves an indexical barrier theorem, according to which sets of non-indexical sentences do not entail (except under specified special circumstances) indexical sentences. It surveys the usual difficulties for this kind of project, as well some that are specific to the case of indexicals, and adapts the strategy of Restall and Russell's "Barriers to Implication" to overcome these. At the end of the paper a reverse barrier theorem is also proved, according to…Read more
  •  6
    New Waves in Philosophical Logic (edited book)
    with Greg Restall
    Palgrave-Macmillan. 2012.
    Machine generated contents note: -- Series Editors' PrefaceAcknowledgementsNotes on ContributorsHow Things Are Elsewhere; W. Schwarz Information Change and First-Order Dynamic Logic; B.Kooi Interpreting and Applying Proof Theories for Modal Logic; F.Poggiolesi & G.Restall The Logic(s) of Modal Knowledge; D.Cohnitz On Probabilistically Closed Languages; H.Leitgeb Dogmatism, Probability and Logical Uncertainty; B.Weatherson & D.Jehle Skepticism about Reasoning; S.Roush, K.Allen & I.HerbertLessons …Read more
  •  224
    Metaphysical analyticity and the epistemology of logic
    Philosophical Studies 171 (1): 161-175. 2014.
    Recent work on analyticity distinguishes two kinds, metaphysical and epistemic. This paper argues that the distinction allows for a new view in the philosophy of logic according to which the claims of logic are metaphysically analytic and have distinctive modal profiles, even though their epistemology is holist and in many ways rather Quinean. It is argued that such a view combines some of the more attractive aspects of the Carnapian and Quinean approaches to logic, whilst avoiding some famous p…Read more
  •  53
    In his recent Philosophers’ Imprint paper “The (mostly harmless) inconsistency of knowledge attributions” [Weiner, 2009], Matt Weiner argues that the semantics of the expression “knows that”, as it is used in attributions of knowledge like “Hannah knows that the bank will be open,” are inconsistent, but that this inconsistency is “mostly harmless.” He presents his view as an alternative to the invariantist, contextualist and relativist approaches currently prevalent in the literature, (e.g. [Sta…Read more
  •  43
    An important part of learning to fight is learning to overcome psychological barriers against harming others. Though there are some interesting exceptions, most human beings experience signicant internal resistance to doing harm to other people. (Marshall 1947, Grossman 1995, Morton 2004, Jensen 2012) Whatever its moral properties, this reluctance to harm can compromise the ability to fighteffectively. Hence one might think that combat training should help trainees overcome such barriers. Howeve…Read more
  •  314
    The analytic/synthetic distinction
    Philosophy Compass 2 (5). 2007.
    Once a standard tool in the epistemologist’s kit, the analytic/synthetic distinction was challenged by Quine and others in the mid-twentieth century and remains controversial today. But although the work of a lot contemporary philosophers touches on this distinction – in the sense that it either has consequences for it, or it assumes results about it – few have really focussed on it recently. This has the consequence that a lot has happened that should affect our view of the analytic/synthetic d…Read more
  •  122
    In defence of Hume’s law
    In Charles Pigden (ed.), Hume on Is and Ought, Palgrave Macmillan. 2010.
    An argument defending the view that one cannot derive an ought from an is against the usual (suspect) counterexamples.
  •  168
    One true logic?
    Journal of Philosophical Logic 37 (6). 2008.
    This is a paper about the constituents of arguments. It argues that several different kinds of truth-bearer may be taken to compose arguments, but that none of the obvious candidates—sentences, propositions, sentence/truth-value pairs etc.—make sense of logic as it is actually practiced. The paper goes on to argue that by answering the question in different ways, we can generate different logics, thus ensuring a kind of logical pluralism that is different from that of J. Beall and Greg Restall