El artículo trata de la correspondencia entre María Zambrano y Alfonso Reyes, especialmente de una “Carta abierta” de la filósofa española, que expresa su descontento con el entusiasmo que Reyes había expresado durante toda su vida intelectual sobre Goethe. Las opiniones de Zambrano al respecto parecen irracionales (Goethe no puede ser gran poeta porque no experimentaba la tragedia existencial). Sin embargo, si se conectan con sus posiciones expresadas en Filosofía y poesía, texto escrito durante su estancia en México, cobran un sentido más trascendental. La pequeña polémica acerca de Goethe podrá ser reubicada, entonces, en el contexto de racionalismo e irracionalismo filosóficos en el sentido de Karl Popper. Abstract This article shows that the 1954 dispute between María Zambrano and Alfonso Reyes about Goethe has to be seen as a consequence of the studies of the Spanish philosopher in the field of the interrelation between poetry and philosophy. In the dispute, Reyes seems to represent a rational position, while Zambrano appears to follow an irrational aesthetics originated by German and English romanticism. When applying Karl Popper’s ideas about rationalism and irrationalism, the result is a different constellation: Zambrano as representative of rational and open thinking, Reyes the promoter of a poetic system based solely on the concept of “great man”, developed in literary criticism by Paul Bénichou, which enabled him to see Goethe as a personality that fuses life and work. This interpretation of Goethe is, by the way, predominant in Spanish-speaking cultures, as Udo Rukser showed in his classical study.