The objectivity of logic and the problem of circularity

Abstract

Two common characterizations of logic seem to conflict. First, reasoning is a social activity: it is something we do together, making claims, denying others, and assessing their justifications. Second, logical norms are objective: the correctness of any logical argument is not merely a matter of perspective or convention. Yet how could norms that are bound to our practices somehow transcend those practices? I resolve this apparent tension using resources from “normative pragmatism,” a strand of pragmatism that aims to account for (not necessarily deflate) epistemic norms. I argue, in short, that the objectivity of logic can be explained by appeal to its fundamental role in our discursive practices.

To believe in logic’s objectivity just is to believe that certain facts about how we ought to reason cannot be reduced to facts about how we think we ought to reason or how we do reason. In Chapters 1–3, I clarify this thesis and argue that realist accounts of logic cannot provide a satisfactory explanation. In Chapters 4–6, I articulate a normative-pragmatist account of logic, focusing on the expressive role of logical vocabulary. Motivated by concerns of circularity, I shift the focus from validity to more fundamental logical norms, such as incompatibility and entailment. I argue that, without such norms, we could not engage in reasoning at all; and without their objectivity, we could not make sense of diversity in our rational practices, nor identify or resolve disagreements among reasoners. In Chapters 7–8, I intervene in two debates: the Adoption Problem concerning logical inference and the possibility of feminism- inspired logical pluralism.

The work’s main contribution is to demonstrate that approaching logic from a social perspective does not require abandoning its objectivity. In fact, doing so can shine new light on important issues, including logical circularity, normativity, and pluralism.

Date of Award	2 Dec 2026
Original language	English
Awarding Institution	University of St Andrews University of Stirling
Supervisor	Greg Restall (Supervisor) & Crispin Wright (Supervisor)