Pathology. Psychosis. Schizophrenia. These words often prove inseparable from the life and work of Robert Walser, who retreated to the sanatoria of Switzerland with a diagnosis of schizophrenia. In so doing, he came to embody our romantic image of the outsider, perhaps more fully than any other German-language writer of the twentieth century. This book takes Walser’s 1929 diagnosis as its point of departure and provides a cognitive study of the author’s writing. Clinical models of schizophrenic cognition from phenomenological psychology guide the analysis, and the book illustrates that underneath Walser’s literary production there is a cognitive process that is marked by the psychological concepts of hyperreflexivity and a loss of common sense. The book addresses four primary elements of Walser’s writing, including his flâneur texts, his singular prose, moments of stasis and epiphany in his writing, and the sense of psychological jeopardy that appears repeatedly in his work. This study proposes a new aetiology for Walser’s prose, one rooted in uncommon cognition. At the same time, it offers a bridge between two trends in Walser scholarship: one which has focused on his hospitalization and diagnosis of schizophrenia, and another that has stressed his unique literary style.