摘要：This paper presents a study of Articles 184, 185 and 186 of the Brazilian Constitution in order to identify, describe and analyse the senses and the argumentative orientation found in such articles regarding to the social function of rural property and its legal implications. We will investigate what the legislator’s choices indicate, when establishing expropriation for the purposes of agrarian reform, (Art 184), defining the properties that are susceptible to expropriation (Art.185) and establishing what concerns the fulfilment of the social function of the agricultural property (Art.186). The analyses are based on studies of the Theory of Argumentation in Language, postulated by Ducrot (1884) and by Anscombre & Ducrot (1997). For Ducrot, the argument is in the language. The words of the language bring in themselves an argument that guides the discourse and the linguistic choices entail an argumentative orientation. The study is also supported by authors who deal with agrarian law (Carrozza and Zeledón, 1990; Scaff, 2005; Bueno, 2017) and the vagueness of the legal norm (Santos, 2002). The analysis of the linguistic marks of the mentioned articles allows to observe that the vagueness of the senses implies incoherence in the argumentative orientation of the constitutional text and can have negative consequences for the decidibility in concrete cases.
关键词：argumentação; vagueza; Constituição Federativa do Brasil; função social; imóvel rural.
