Under great financial pressure and personal distress, Broch composed with extreme haste in the summer of 1933 a short novel that he would later famously reject as “ein mieses Buch, das verscharrt und vergessen bleiben soll!”(a rotten book that must stay buried and forgotten!). Although Die Unbekannte Größewas Broch’s greatest commercial success, the author repeatedly disparaged it in correspondence, and most scholars of Broch’s literature have followed his lead in dismissing it as aesthetically and formally weak.Since around 1999, however, interest in Broch’s second novel has grown significantly, because it provides insight into his relationship to mathematics and the natural sciences, especially modern physics, and further analysis has revealed it to be the most direct and transparent literary manifestation of Broch’s philosophy. A sparse but expanding body of secondary literature seeks to understand the role of Die Unbekannte Größe in Broch’s greater body of works.

In the novel the somewhat autobiographically conceived doctoral student Richard Hieck attempts to order his life by means of rational inquiry and strives toward comprehensive mathematical and scientific knowledge, with the express goal of one day achieving Erkenntnis (a central concept to Broch that cannot be translated to a single word in English and represents a complex mix of “knowledge,” “insight,” “perception,” “awareness,” and “cognition”).Richard believes that Erkenntnis is attainable through purely rational means and strives to understand all of life in mathematical terms. Through a series of events that occur outside the control of reason, however, he comes to realize that there are irrational elements in life that cannot be repressed and without acknowledgment of which true Erkenntnis cannot occur. Richard lives in a cramped apartment in a German-speaking university town with his mother; his sister Susanne, five years his junior; and his brother, Otto, another five years younger.There are two additional siblings, Rudolf and Emilie; they are between Richard and Susanne in age, and both have left town. The father died many years prior to the opening of the narrative.