Skeptical Acceptance
Given an AF and an argument , decide whether is skeptically accepted, i.e. contained in every -extension of . If has no -extension, every argument counts as skeptically accepted.
Reference
Dvořák, W. & Dunne, P.E. (2018). Computational Problems in Formal Argumentation and their Complexity. In: Baroni, P., Gabbay, D., Giacomin, M. & van der Torre, L. (eds.), Handbook of Formal Argumentation, Vol. 1, Chapter 13, pp. 631–688. College Publications.