Accepting a Logic, Accepting a Theory
Timothy Williamson (Oxford University, Yale University)

May 27, 2021, 5:00pm - 7:00pm
Dianoia Institute of Philosophy, Australian Catholic University

East Melbourne


Australian Catholic University

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Dianoia Annual Seminar in Logic & Language

Title: Accepting a Logic, Accepting a Theory

Abstract: The lecture defends the possibility, though not the desirability, of accepting an alternative logic, on the basis of an anti-exceptionalist view of logic, on which coming to accept a new logic is a special case of coming to accept a new scientific theory. A distinction between folk logic and scientific logic is modelled on the distinction between folk physics and scientific physics. The importance of not confusing logic with metalogic in applying this distinction is emphasized. Defeasible inferential dispositions are shown to play a major role in theory acceptance in logic and mathematics as well as in natural and social science. Like beliefs, such dispositions are malleable in response to evidence, though not simply at will. Consideration is given to the Quinean objection that accepting an alternative logic involves changing the subject rather than denying the doctrine. The objection is shown to depend on neglect of the social dimension of meaning determination, akin to descriptivism about proper names and natural kind terms. Normal standards of interpretation indicate that disputes between classical and non-classical logicians are genuine disagreements.

The time for the event is Thursday 27 May, 5:00-6:45 pm (Melbourne) / 8:00-9:45 am (London) / 12:00-1:45 am (Los Angeles).

This event will be held over Zoom. To receive the link and password, please register at For any questions, please email [email protected]

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May 27, 2021, 5:00pm +10:00

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Australian Catholic University
University of Pittsburgh
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