ABSTRACT: It is important to say that a decisive part within De Martino’s process of intellectual becoming is represented both by the evolution of his thinking process starting from theories and concepts that he initially embraces, which he later abandons or nuances, but also by his relationship with other intellectuals, that is the dialogue he had with these and the extremely fruitful role of reciprocate criticism. It is what we actually find within the things exposed above. A remarkable thing to notice is the dialogue between Ernesto de Martino and Mircea Eliade. But before formulating some conclusive remarks of these reciprocate exchange of impressions and objections on the theoretical level regarding their implications on De Martino’s work, it is important to bear in mind some substantial aspects of De Martino’s major influences prior to his dialogue with Eliade. Starting from his initial argument, which he expressed when he was young, on the importance of the necessity of exploring the world of mystery, but also from the major loss of western thinking of ignoring this subject, De Martino structures his analytical work on Benedetto Croce’s conceptual basis. After internalizing Croce’s perspective on history, even on mystery, De Martino takes over on Croce’s basic idea of the mystery’s own existence as imaginary abstract category, which reason cannot define accurately, but particularly emphasizes on the western world accumulation of prejudices (pre-conceived ideas) on this topic. Moreover, De Martino notices the essence of Croce’s idea, which he takes and applies conscientiously as methodologic landmark of his entire work: the fact that, the irrational, which is an intricate aspect linked to the “mystery” theme, operates on the level of history. KEYWORDS: mystery, the irrational, history, abstract category, intellectual