This article explores how psychological categories linked to the mental level, such as genius, mediocrity, and intellectual superiority, were directly intertwined with political discourse in the early 20th century. To illustrate this, I analyze El Hombre Mediocre (The Mediocre Man) published in 1913 by José Ingenieros, seemingly as a direct critique of the law for free democratic elections in Argentina sanctioned in 1912. The book's main argument drew on psychological categories to explain that democracy was, in fact, a poor choice in government. Ingenieros' main concern was that the population was mostly mediocre and therefore unable to govern or elect a suitable candidate to run the country. One category that stood out in his analysis was the "genius." This term was reserved for men who demonstrated exceptional intelligence and remarkable morals and ideals. The methodology used in this article is based on the qualitative and interpretative analysis of bibliographical sources (which include books of essays, scientific papers, and books aimed at lay audiences) from the perspective of intellectual history and the critical history of psychology. I argue that Ingenieros' book served as a political essay founded on a comprehensive scientific explanation, even if it was aimed at a lay audience. This analysis shows the productivity of psychological categories referring to giftedness, intelligence, and talent, in adulthood for assessing political movements and planning new imagined societies through the history of psychology. (PsycInfo Database Record (c) 2023 APA, all rights reserved).