Dispositionalism’s (grand)daddy issues: time travelling and perfect masks

Abstract There is a tension between Dispositionalism––the view that all metaphysical modality grounded in actual irreducible dispositional properties––and the possibility of time travel. This due to fact Dispositionalism makes it much harder solve potentiality-based version grandfather paradox. We first present paradox, stating following theses are inconsistent: 1) travel possible, 2) powers fully ground modality, 3) self-defeating actions impossible, 4) time-travellers retain their intrinsic upon time-travelling, and 5) ordinary agents with basic potentialities. then consider number potential solutions, find them wanting. argue impossibility performing action acts as necessary perfect mask––while time-travel lets us “slip” potentiality under mask, thus generating contradiction. conclude considering what options for dispositionalist.