BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Teresa Kouri Kissel (Old Dominion University) DTSTART:20230928T180000Z DTEND:20230928T190000Z DTSTAMP:20260423T035916Z UID:OLS/136 DESCRIPTION:Title: Pr oof-Theoretic Pluralism and Harmony\nby Teresa Kouri Kissel (Old Domin ion University) as part of Online logic seminar\n\n\nAbstract\nAbstract: F errari and Orlandelli (2019) propose that an admissibility condition on a proof-theoretic logical pluralism be that the logics in question must be h armonious\, in the sense of Belnap (1962). This means that they must have connectives which are unique and conservative. This allows them to develop an innovative pluralism\, which shows variance on two levels. On one leve l\, we have a pluralism at the level of validity alone\, like that in Rest all (2014). But\, thanks to the Ferrari and Orlandelli system\, which was developed in response to some concerns of Kouri (2016)\, we can add a seco nd level and admit some logics which do not share connective meanings\, an d hence have different operational rules. This allows for us to have a plu ralism at two levels: the level of validity and the level of connective me anings.\n\nHere\, I will show that we can extend the system one step furth er\, and induce a three-level logical pluralism. The first and second leve ls remain as suggested by Ferrari and Orlandelli (2019)\, but we can allow for multiple notions of uniqueness in the definition of Belnap-harmony\, or multiple notions of harmony writ large. Either of these options generat es a pluralism at the level of our admissibility conditions. This generate s a pluralism at three levels: validity\, connective meanings\, and admiss ibility conditions. But it still preserves the spirit of the Ferrari and O rlandelli (2019) solution: harmony remains as the admissibility constraint across the board\, and so the original worries of Kouri (2016) are still put to rest and the original Beall and Restall (2006) criteria for admissi ble logics are still met.\n LOCATION:https://researchseminars.org/talk/OLS/136/ END:VEVENT END:VCALENDAR