A reflection about the other proves to be stimulating. This article is divided into two parts. At first, it establishes a generic theoretical and conceptual framework of the relations between philosophy and history, highlighting the importance of authors such as Roger Chartier (who has done readings of Foucault and Certeau). In the second part this article analyzes Razão e História (Introdução a um problema) written by Magalhães Godinho. This degree thesis (1940) thematizes this neopositivism in previous works of Abel Salazar, Delfim Santos or subsequent essays, authored by Vasco Magalhães-Vilhena or Egídio Namorado, looking to set up a critical rationalism.