© 2019. Leite, Marli Quadros. This is a research/review paper, distributed under the terms of the Creative Commons Attribution- Noncommercial 3.0 Unported License http://creativecommons.org/licenses/by-nc/3.0/), permitting all non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Global Journal of HUMAN-SOCIAL SCIENCE: G Linguistics & Education Volume 19 Issue 10 Version 1.0 Year 2019 Type: Double Blind Peer Reviewed International Research Journal Publisher: Global Journals Online ISSN: 2249-460x & Print ISSN: 0975-587X Rationalist Theory in the Postillas de Grammatica Geral of Francisco Sotero dos Reis By Leite, Marli Quadros University of São Paulo Abstract- Our goal in this article is to analyze the Postillas de grammmaticageralapplicada á lingua portugueza pela analyse dos classicos, ouguia para a construcçãoportugueza (Apostilles of General Grammar as Applied to the Portuguese Language Through the Analysis of the Classics, or, a Guide to Portuguese Construction) (1868 [1862]), by Francisco Sotero dos Reis (1800-1871), in order to investigate to what extent the author applies the foundations of the general theory to the exploration and interpretation of excerpts syntax from literary texts of the Portuguese language collected for analysis. We will be working with theory, methods and techniques from the História das IdeiasLinguisticas (History of Linguistic Ideas) (Auroux 2006, 2009; Colombat, Fournier, Puech 2017; Leite 2018), which leads us to treat the grammatical fact selected for analysis as an effect, and as a cause the theory that served the interpretation given by the grammarian to that fact. Keywords: philosophical grammar, brazilian philosophical grammar, portuguese language, general theory, traditional theory, retrospective horizons, history of linguistic ideas. GJHSS-G Classification: FOR Code: RationalistTheoryinthePostillasdeGrammaticaGeralofFranciscoSoterodosReis Strictly as per the compliance and regulations of: 339999