Between 20 th th Century World Wars, Japan became intellectual scenario for the development of important studies on the press and the theory of journalism. The transformation of journalism in big business provoked a rich discussion about it in academic and professional circles. The article presents the first analysis in Portuguese about this phenomenon, frequently unnoticed even in more advanced scholarly centers. The period studied in the article extends from 1920 to 1937. The initial section analyses the origins and historical context of the phenomenon. The three following sections report the scientific and philosophical trends that guided its development. The conclusion points to the circumstances of their break, occurred amid the advancement of military dictatorship and the escalation of war against China.