This paper defends a reading of Wittgenstein’s philosophy of mathematics in the Lectures on the Foundation of Mathematics as a radical conventionalist one, whereby our agreement about the particular case is constitutive of our mathematical practice and ‘the logical necessity of any statement is a direct expression of a convention’ (Dummett 1959, p. 329). -/- On this view, mathematical truths are conceptual truths and our practices determine directly for each mathematical proposition individually whether it is true or false. Mathematical truths (...) are thus not consequences of a prior adoption of a convention or rules as orthodox conventionalism has it. -/- The goal of the paper is not merely exegetical, however, and argues that radical conventionalism can withstand some of the most difficult objections that have been brought forward against it, including those of Dummett himself, and thus that radical conventionalism has been prematurely excluded from consideration by philosophers of mathematics. (shrink)

In his groundbreaking book, Thin Objects, Linnebo (2018) argues for an account of neo-Fregean abstraction principles and thin existence that does not rely on analyticity or conceptual rules. It instead relies on a metaphysical notion he calls “sufficiency”. In this short discussion, I defend the analytic or conceptual rule account of thin existence.

Burgess (1997), building on Quine (1953), convincingly argued that claims in quantified modal logic cannot be understood as synonymous with or logically equivalent to claims about the analyticity of certain sentences. According to modal normativism, metaphysically necessary claims instead express or convey our actual semantic rules. In this paper, I show how the normativist can use Sidelle’s (1992a, 1995) neglected work on rigidity to account for two important phenomena in quantified modal logic: the necessity of identity and the substitutivity of (...) identicals into modal contexts. (shrink)

Once upon a time, logical conventionalism was the most popular philosophical theory of logic. It was heavily favored by empiricists, logical positivists, and naturalists. According to logical conventionalism, linguistic conventions explain logical truth, validity, and modality. And conventions themselves are merely syntactic rules of language use, including inference rules. Logical conventionalism promised to eliminate mystery from the philosophy of logic by showing that both the metaphysics and epistemology of logic fit into a scientific picture of reality. For naturalists of all (...) stripes, this was paradise. Alas, paradise was lost. By the end of the twentieth century, logical conventionalism had been almost universally abandoned. But more recently, it has been revitalized. This chapter provides an overview of logical conventionalism and its history, clears away misunderstandings, and briefly responds to both the canonical objections to conventionalism (from Quine, Dummett, Boghossian, and many others) as well as new objections (from Field and Golan). From paradise lost, to paradise regained: logical conventionalism is back. (shrink)

I consider the claim that analytic statements are "true in virtue meaning", giving the claim a ground-theoretic interpretation.

According to linguistic conventionalism, necessities are to be explained in terms of the conventionally adopted rules that govern the use of linguistic expressions. A number of influential arguments against this view concerns the ‘Truth-Contrast Thesis’. This is the claim that necessary truths are fundamentally different from contingent ones since they are not made true by ‘the facts’. Instead, they are supposed to be something like ‘true in virtue of meaning’. This thesis is widely held to be a core commitment of (...) the conventionalist position, and the view is frequently rejected on the grounds that this thesis is untenable. I argue that this line of reasoning is mistaken. While the thesis should be rejected, it is not, I argue, entailed by linguistic conventionalism – nor was it invariably accepted by the paradigmatic conventionalists. (shrink)

Distinctively mathematical explanations (DMEs) explain natural phenomena primarily by appeal to mathematical facts. One important question is whether there can be an ontic account of DME. An ontic account of DME would treat the explananda and explanantia of DMEs as ontic structures and the explanatory relation between them as an ontic relation (e.g., Pincock 2015, Povich 2021). Here I present a conventionalist account of DME, defend it against objections, and argue that it should be considered ontic. Notably, if indeed it (...) is ontic, the conventionalist account seems to avoid a convincing objection to other ontic accounts (Kuorikoski 2021). (shrink)

The positivists defined analyticity as truth in virtue of meaning alone and advocated the view that the notion of analyticity so defined is co-extensive with both the notion of an a priori truth an...

Wittgenstein and the logical positivists attempted to explain logical necessity in terms of linguistic conventions. It is often thought that their respective accounts have been conclusively refuted by objections from Quine, Dummett and others. We argue that this verdict is premature. Several of the most popular anti‐conventionalist arguments fail, partly because they misconstrue the idea of truth by convention in Wittgenstein and/or logical positivism. Correctly understood, conventionalism claims that, given certain linguistic conventions, some sentences are unconditionally true, that is true (...) irrespective of how the world happens to be. This claim is difficult to deny, and the corresponding conventionalism about logical necessity remains a viable position. (shrink)

The positivists’ notion of truth in virtue of meaning presupposes that the truth of certain sentences can be explained merely by reference to semantic rules. The currently most popular objection to the notion denies the possibility of such semantic explanations, on the grounds that semantic rules can only explain what a sentence says, but not whether what a sentence says is true. Though recent critics of the objection have insisted that semantic rules do explain the truth of certain sentences, the (...) very notion of a semantic explanation is often left unclear. This paper proposes to define the notion of semantic explanation as a valid argument that derives the truth of a sentence from accepted semantic rules. The account offered will then be used to respond to some of the most pressing objections to the idea of truth in virtue of meaning. (shrink)

[Use code AUFLY30 for 30% off on the OUP website.] One central aim of science is to provide explanations of natural phenomena. What role(s) does mathematics play in achieving this aim? How does mathematics contribute to the explanatory power of science? Rules to Infinity defends the thesis, common though perhaps inchoate among many members of the Vienna Circle, that mathematics contributes to the explanatory power of science by expressing conceptual rules, rules which allow the transformation of empirical descriptions. Mathematics should (...) not be thought of as describing, in any substantive sense, an abstract realm of eternal mathematical objects, as traditional platonists have thought. In Rules to Infinity, this view, which I call mathematical normativism, is updated with contemporary philosophical tools, and it is argued that normativism is compatible with mainstream semantic theory. This allows the normativist to accept that there are mathematical truths, while resisting the platonistic idea that there exist abstract mathematical objects that explain such truths. Furthermore, Rules to Infinity defends a particular account of the distinction between scientific explanations that are in some sense distinctively mathematical – those that explain natural phenomena in some uniquely mathematical way – and those that are only standardly mathematical, and it lays out desiderata for any account of this distinction. Normativism is compared with other prominent views in the philosophy of mathematics such as neo-Fregeanism, fictionalism, conventionalism, and structuralism. Rules to Infinity serves as an entry point into debates at the forefront of philosophy of science and mathematics, and it defends novel positions in these debates. (shrink)