This article analyzes the role Nietzsche's philosophy played in Ramón Gómez de la Serna's (1888-1963) journey toward the Avant-Garde in the early years between 1907 and 1911. Gómez de la Serna's readings of Thus Spoke Zarathustra and Ecce Homo were decisive in defining his sense of self in concepts of truth and falsity. The concern for a self-critical and increasingly "authentic" subjectivity leads Ramón irrevocably to an autobiographical mode of writing in a Nietzschesit sense. However, Ramón's concept of authenticity progressively approached autobiography as a truthful expression of something deeper and more personal: one's "vitalismo." Thus, facts, bearing witness, personal history, and linear temporality need not be privileged in autobiography. Instead, what was truthful cut much deeper into the self and entailed how it overcame its circumstance to locate something more authentic in the presentness of experience.