Starting from Descartes, knowing that p(where p is any proposition) means for an epistemic agent to succeed in eliminatinga series of logical possibilities incompatible with the truth of p. Such an epistemological approach is de facto a tribute to skepticism (human knowledge becomes lack of doubt) even when one does not expect to be skeptical. Otherwise, it transforms every case of knowledge into a sophisticated case of modal knowledge, and epistemology ends up with mainly concerning possible worlds. The course examines the relationship between knowledge and the notion of logical possibility, initially investigating the logical structure of skepticism, as well as the recent attempt to drain, or confine, its effectiveness by redefining the agent's modal perspective. In particular, it will be support the thesis whereby the agent's negative ability to eliminate relevant counter-possibilities and neglect the irrelevant ones is an insufficient epistemic barometer, unless it is not accompanied by her positive ability to imagine (realized) possibilities, connected with one's true beliefs. This ability brings the agent into a properly abductive perspective, completely overlooked by contemporary epistemology because of its skeptical curvature. Then, the relationship between abduction and modality will be studied, defining a proper logic for abduction, which touches not only epistemology, but also philosophy of science and the theory of human reasoning.
gain understanding of contemporary issues of epistemology (skepticism and epistemic contextualism), modality and abduction.
D. Lewis, ''Scorekeeping in a language game''. Journal of Philosophical Logic, 8 (1979) pp. 339–359.
D. Lewis, ''Elusive Knowledge''. Australasian Journal of Philosophy 74 (1996), pp. 549–567.