•  30
    Knot much like tonk
    Synthese 200 (149): 1-14. 2022.
    Connectives such as Tonk have posed a significant challenge to the inferentialist. It has been recently argued that the classical semanticist faces an analogous problem due to the definability of “nasty connectives” under non-standard interpretations of the classical propositional vocabulary. In this paper, we defend the classical semanticist from this alleged problem.
  •  28
    Shrieking, Shrugging, and the Australian Plan
    Notre Dame Journal of Formal Logic 63 (2). 2022.
    We observe that Jc Beall’s shrieking and shrugging strategy gives us an opportunity to reflect on the Australian plan for negation in FDE, a basic subclassical logic that is used in Beall’s argument for subclassical logics. An implication of our observation is applied to a recent defense of the Australian plan for negation by Francesco Berto and Greg Restall.
  •  35
    Haecceitism and counterpart theory
    Theoria 88 (6): 1163-1179. 2022.
    David Lewis argues at length against haecceitism and goes as far as claiming that, on a certain counterpart-theoretic construal, the doctrine is unintelligible or inconsistent. I argue, contra Lewis, that both qualitative and non-qualitative counterpart theory are in fact committed to haecceitism, but that this commitment is harmless since what is really at stake for a counterpart theorist such as Lewis are more general supervenience claims that are independent of haecceitism. I further argue th…Read more
  •  29
    Truthmakers or truthmaking supervenience?
    Synthese 198 (10): 9821-9839. 2020.
    I argue that counterpart theory is incompatible with truthmaking supervenience, the thesis that truth supervenes on what there is and how things are. I further argue that David Lewis’s “qua” strategy for providing ontologically innocent and Humean-friendly truthmakers for predications faces a number of difficulties. I propose and assess various solutions to those difficulties, each of which comes at the cost of sacrificing one of the two main virtues of the qua strategy.
  •  42
    On Moore’s Notion of Proof
    Canadian Journal of Philosophy 50 (3): 313-321. 2020.
    Much has been said about Moore’s proof of the external world, but the notion of proof that Moore employs has been largely overlooked. I suspect that most have either found nothing wrong with it, or they have thought it somehow irrelevant to whether the proof serves its antiskeptical purpose. I show, however, that Moore’s notion of proof is highly problematic. For instance, it trivializes in the sense that any known proposition is provable. This undermines Moore’s proof as he conceives it since i…Read more
  •  338
    A Modal Account of Essence
    Metaphysics 3 (1): 17-32. 2020.
    According to the simple modal account of essence, an object has a property essentially just in case it has it in every world in which it exists. As many have observed, the simple modal account is implausible for a number of reasons. This has led to various proposals for strengthening the account, for example, by adding a restriction to the intrinsic or sparse properties. I argue, however, that these amendments to the simple modal account themselves fail. Drawing on lessons from these failures, I…Read more
  •  62
    Classical Negation and Expansions of Belnap–Dunn Logic
    Studia Logica 103 (4): 825-851. 2015.
    We investigate the notion of classical negation from a non-classical perspective. In particular, one aim is to determine what classical negation amounts to in a paracomplete and paraconsistent four-valued setting. We first give a general semantic characterization of classical negation and then consider an axiomatic expansion BD+ of four-valued Belnap–Dunn logic by classical negation. We show the expansion complete and maximal. Finally, we compare BD+ to some related systems found in the literatu…Read more
  •  53
    More on Empirical Negation
    with Hitoshi Omori
    In Rajeev Goré, Barteld Kooi & Agi Kurucz (eds.), Advances in Modal Logic, Volume 10, Csli Publications. pp. 114-133. 2014.
    Intuitionism can be seen as a verificationism restricted to mathematical discourse. An attempt to generalize intuitionism to empirical discourse presents various challenges. One of those concerns the logical and semantical behavior of what has been called ' empirical negation'. An extension of intuitionistic logic with empirical negation was given by Michael De and a labelled tableaux system was there shown sound and complete. However, a Hilbert-style axiom system that is sound and complete was …Read more
  •  1082
    On the Humphrey Objection to Modal Realism
    Grazer Philosophische Studien 95 (2): 159-179. 2018.
    An intuitive objection to modal realism is that merely possible worlds and their inhabitants seem to be irrelevant to an analysis of modality. Kripke originally phrased the objection in terms of being concerned about one’s modal properties without being concerned about the properties one’s other-worldly counterparts have. The author assesses this objection in a variety of forms, and then provides his own formulation that does not beg the question against the modal realist. Finally, the author co…Read more
  •  30
    Negation in context
    Dissertation, University of St Andrews. 2011.
    The present essay includes six thematically connected papers on negation in the areas of the philosophy of logic, philosophical logic and metaphysics. Each of the chapters besides the first, which puts each the chapters to follow into context, highlights a central problem negation poses to a certain area of philosophy. Chapter 2 discusses the problem of logical revisionism and whether there is any room for genuine disagreement, and hence shared meaning, between the classicist and deviant's respe…Read more
  •  85
    There is More to Negation than Modality
    Journal of Philosophical Logic 47 (2): 281-299. 2018.
    There is a relatively recent trend in treating negation as a modal operator. One such reason is that doing so provides a uniform semantics for the negations of a wide variety of logics and arguably speaks to a longstanding challenge of Quine put to non-classical logics. One might be tempted to draw the conclusion that negation is a modal operator, a claim Francesco Berto, 761–793, 2015) defends at length in a recent paper. According to one such modal account, the negation of a sentence is true a…Read more
  •  91
    Intrinsicality and counterpart theory
    Synthese 193 (8). 2016.
    It is shown that counterpart theory and the duplication account of intrinsicality —two key pieces of the Lewisian package—are incompatible. In particular, the duplication account yields the result that certain intuitively extrinsic modal properties are intrinsic. Along the way I consider a potentially more general worry concerning certain existential closures of internal relations. One conclusion is that, unless the Lewisian provides an adequate alternative to the duplication account, the reduct…Read more
  •  33
    Classical and Empirical Negation in Subintuitionistic Logic
    with Hitoshi Omori
    In Lev Beklemishev, Stéphane Demri & András Máté (eds.), Advances in Modal Logic, Volume 11, Csli Publications. pp. 217-235. 2016.
    Subintuitionistic (propositional) logics are those in a standard intuitionistic language that result by weakening the frame conditions of the Kripke semantics for intuitionistic logic. In this paper we consider two negation expansions of subintuitionistic logic, one by classical negation and the other by what has been dubbed “empirical” negation. We provide an axiomatization of each expansion and show them sound and strongly complete. We conclude with some final remarks, including avenues for fu…Read more
  •  287
    An interesting question is whether deflationism about truth (and falsity) extends to related properties and relations on truthbearers. Lionel Shapiro (2011) answers affirmatively by arguing that a certain deflationism about truth is as plausible as an analogous version of deflationism about logical consequence. I argue that the argument fails on two counts. First, it trivializes to any relation between truthbearers, including substantive ones; in other words, his argument can be used to establis…Read more
  •  104
    Empirical Negation
    Acta Analytica 28 (1): 49-69. 2013.
    An extension of intuitionism to empirical discourse, a project most seriously taken up by Dummett and Tennant, requires an empirical negation whose strength lies somewhere between classical negation (‘It is unwarranted that. . . ’) and intuitionistic negation (‘It is refutable that. . . ’). I put forward one plausible candidate that compares favorably to some others that have been propounded in the literature. A tableau calculus is presented and shown to be strongly complete