Presupposition is surely one of the most debated notions in the linguistic and philosophical literature. Historically, there are two main theoretical approaches to presuppositions. According to the first one, the semantic view, presuppositions are semantic implications, that is, truth-conditional relations between propositions and statements. In this sense, presuppositions are considered properties of sentences and a presupposed proposition is a necessary condition for the truth of the presupposing statement. In the second approach, the pragmatic view, presuppositions are not properties of sentences but rather properties of speakers or of linguistic performances given a certain context of utterance. From this view, a presupposed proposition...