ProjectBeing Logical: On Possible Ways to Expand our Understanding of Logicality

Basic data

Being Logical: On Possible Ways to Expand our Understanding of Logicality
01/09/2024 to 31/08/2027
Abstract / short description:
In spite of the central role played by the traditional view of a logic as a language plus a consequence relation, understood as a set of (valid) inferences, as of today there is no agreement on which is the right way to characterize a logic. The traditional view has been opposed for different reasons. In particular, some authors have called for either extending the notion of consequence relation to include meta-inferences in the picture, expanding the way to intensionally characterize that set by relaxing the demand that sets of designated values should be an upset, or adding more items to the n-tuple that characterize a logic. The goal of the project is to propose a novel picture of logic that does justice to these different perspectives. Its major contribution will be the development of a new conception of what a logic is, with the capacity to discriminate between what intuitively seem to be different logics. The project will begin by criticizing the traditional view in connection with an anti-exceptionalist and pluralist point of view. Relaxing the constraints imposed on a logic allows the development of more satisfactory conceptions of paradoxical phenomena while also representing the norms towards sentences involving other epistemic attitudes besides acceptance, such as rejection and suspension of judgment. The main part of the project consists of developing a novel conception of what a logic is, meeting the desiderata identified in the first part of the project. The approach will be pluralist in spirit and will aim at providing a multi-standard presentation of an extensional way to characterize a logic. It will look for an understanding of validity, anti-validity and other ways to categorize (meta)inferences of a logic that relate them to some key epistemic attitudes someone who endorses a logic is committed to. On the basis of the proposed understanding of a logic, we will advance a framework in which a logic is not described solely in terms of its validities nor necessarily in terms of upsets of designated values. This novel conception a logic not only considers other properties besides validities, but also includes the meta-inferential realm in the picture. Moreover, as an adequate language for a logic thus defined should include new (meta)inferential constants, in order to better understand the different behaviors of seemingly equivalent logics, we will define our logics in this enriched expressive framework.

Involved staff


Faculty of Science
University of Tübingen
Wilhelm Schickard Institute of Computer Science (WSI)
Department of Informatics, Faculty of Science

Local organizational units

Department of Informatics
Faculty of Science
University of Tübingen


Bonn, Nordrhein-Westfalen, Germany

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