LIRa Session: Sven Rosenkranz

Speaker: Sven Rosenkranz

Date and Time: Thursday, February 25th 2021, 16:30-18:00, Amsterdam time.

Venue: online.

Title: To be in no position to know to be in no position to know: methods, safety, and luminosity.

Abstract. To the best of my knowledge, no epistemic logician seriously entertains the thought that negative introspection holds: clearly, some cases of ignorance go unnoticed. By contrast, many epistemic logicians seem unfazed by extant arguments against positive introspection and continue working with logics at least as strong as S4. There are arguments against positive introspection that rely on the fact that knowledge implies belief. Such arguments can be defused by recasting positive introspection in terms of the factive notion of being in a position to know, where to be in a position to know p, one needn’t believe p. Knowledge requires safe belief, and being in a position to know accordingly requires being in a position to safely believe. There are powerful safety- based arguments against positive introspection, even in its revised formulation. I will not here rehearse these arguments. Instead, I will argue for the claim that the safety requirement poses no threat to ¬K¬Kp → K¬K¬Kp, where ‘K’ is short for ‘One is in a position to know that’. If ¬K¬Kp → K¬K¬Kp holds, ¬K¬Kp encodes a luminous condition. The lead idea driving the argument is that methods for telling if ¬Kp holds are best seen as being functionally dependent on the best methods for telling if p holds, and as being lopsided in that they are not, at the same time, methods for telling if Kp holds. Accordingly, I must say a lot about methods first. Elsewhere I have argued that ¬K¬Kp is necessary and sufficient for one’s having propositional justification for p. If ¬K¬Kp → K¬K¬Kp can be upheld, then this implies that having propositional justification is a luminous condition – an idea that internalists typically cherish but struggle to substantiate. The lesson for the epistemic logician, if any, is that systems weaker than S4 should be devised that accommodate the luminosity of ¬K¬Kp.