Da Costa logics and vagueness

Da Costa logic was proposed by Priest, dualizing the truth condition for negation in intuitionistic Kripke model. In this paper, we propose to use da Costa logic as a logic for vagueness. We consider some extensions of da Costa logic and discuss the formalization of vagueness. We also compare our logics with Diintsch's rough set logic and Lawvere's ideas of modeling vagueness.