Logic, Epistemology and Metaphysics Seminar

Logic, Epistemology and Metaphysics Seminar
2 February 2021, 5.30pm - 7.00pm
Online seminar - Please book using link below

Indicative Conditionals: Probabilities and Relevance

Franz Berto (St Andrews) & Aybüke Özgün (Amsterdam)

Adams’ Thesis has it that the acceptability of a conditional equals the corresponding conditional probability. The Thesis is widely endorsed but arguably false and refuted by empirical research. To fix it, we submit, we need a relevance constraint: we accept a simple conditional ‘If φ, then ψ’ to the extent that (i) the conditional probability p(ψ|φ) is high, provided that (ii) φ is relevant for ψ. How (i) should work is well-understood. It is (ii) that holds the key to improve our understanding of conditionals.

We propose a formal framework giving acceptability and logical closure conditions for simple indicatives: its probabilistic component (i) uses Popper functions; its relevance component (ii) is given via an algebraic structure of topics. We then present the resulting logic of relevant conditionals. We argue that the closure principles (in)validated by the logic are both theoretically desirable and in line with empirical results on how people reason with conditionals.

The Centre for Logic and Language hosts a regular seminar series - the Logic, Epistemology and Metaphysics Forum (LEM). The forum generally meets fortnightly in term time. and is supported by the ERC project Metacognition of Concepts (GA 681422).


Institute of Philsophy
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