• Metaphysical anti-realism is a large and heterogeneous group of views that do not share a common thesis but only share a certain family resemblance. Views as different as mathematical nominalism—the view that numbers do not exist—, ontological relativism—the view that what exists depends on a perspective—, and modal conventionalism—-the view that modal facts are conventional—all are versions of metaphysical anti-realism. As the latter two examples suggest, relativist ideas play a starring role i…Read more
  •  12
    Ontological Expressivism
    In J. T. M. Miller (ed.), The Language of Ontology. 2021.
    Ontological expressivism is the view that ontological existence claims express non-cognitive mental states. I develop a version of ontological expressivism that is modeled after Gibbard’s (2003) norm-expressivism. I argue that, when speakers assess whether, say, composite objects exist, they rely on assumptions with regard to what is required for composition to occur. These assumptions guide their assessment, similar to how norms may guide the assessment of normative propositions. Against this b…Read more
  •  52
    The Metasemantics of Indefinite Extensibility
    Tandf: Australasian Journal of Philosophy 1-18. forthcoming.
    Generality relativism is the view that any domain of quantification can always be expanded. The view promises to resolve a broad range of paradoxes; but without an explanation of how domains expand it sounds very mysterious. Proponents of linguistic versions of generality relativism try to demystify the view by likening domain expansions to semantic change. They think that domains expand when we re-interpret certain terms so that, upon re-interpretation, the quantifiers range over more things. T…Read more
  •  120
    How to engineer a concept
    Philosophical Studies. forthcoming.
    One dimension of cognitive success concerns getting it right: having many true beliefs and no false ones. Another dimension of cognitive success concerns using the right concepts. For example, using a concept of a person that systematically excludes people of certain demographics from its extension is a sort of cognitive deficiency. This view, if correct, tasks inquirers with critically examining the concepts they are using and perhaps replacing those concepts with new and better ones. This task…Read more
  •  103
    Scientific Ontology (review)
    Philosophical Review 129 (1): 144-149. 2020.
  •  56
    Carnap’s defense of impredicative definitions
    Review of Symbolic Logic 12 (2): 372-404. 2019.
    A definition of a property P is impredicative if it quantifies over a domain to which P belongs. Due to influential arguments by Ramsey and Gödel, impredicative mathematics is often thought to possess special metaphysical commitments. It seems that an impredicative definition of a property P does not have the intended meaning unless P already exists, suggesting that the existence of P cannot depend on its explicit definition. Carnap (1937 [1934], p. 164) argues, however, that accepting impredica…Read more
  •  135
    Carnap's Noncognitivism about Ontology
    Noûs 54 (3): 527-548. 2020.
    Do numbers exist? Carnap (1956 [1950]) famously argues that this question can be understood in an “internal” and in an “external” sense, and calls “external” questions “non-cognitive”. Carnap also says that external questions are raised “only by philosophers” (p. 207), which means that, in his view, philosophers raise ”non-cognitive” questions. However, it is not clear how the internal/external distinction and Carnap’s related views about philosophy should be understood. This paper provides a ne…Read more
  • Differenz und Dialog (edited book)
    with H. Schoneville
    Berliner Wissenschafts-Verlag. 2011.