McMaster Philosophy Department Speaker Series Welcomes:
Brent C Odland
A Logic of Epistemic Obligations and the Ethics of Belief
In this presentation, I will show that a multi-modal logic of epistemic obligations, presented by signed prefix semantic tableaux, is strong enough to prove certain principles discussed in the literature on the ethics of belief. Logics of epistemic obligation are not a new topic, however I will show that without inclusion rules, these kinds of system are not capable of proving many principles discussed in the ethics of belief. The logic I propose contains a combination of alethic, epistemic, doxastic, and deontic modalities, each individual of which is captured by a standard, commonly accepted “normal” axiomatization, together with an inclusion scheme. This system is capable of proving the principal of doxastic volunteerism, which many regard as essential to the possibility of an ethics of belief, as well as principles prohibiting self-deception and requiring individuals with special responsibilities to be informed on some circumstance, as we might think of Clifford’s shipowner in his famous example, not to be unjustly ignorant. I close with discussion of possible extensions of this system, like incorporating a logic of action, adding a temporal fragment, or modifying the epistemic fragment to naturalize the epistemic agents in the system, that might allow it to bear on even more notions discussed in the ethics of belief.