Nietzsche scholars generally adopted Kaufmann's opinion, who immediately identified the book as a forgery in a 1952 article. Evidence against the book cited by Kaufmann and later commentators includes anachronisms like a reference to an 1898 incident, incongruous references to
Marxism and the city of
Detroit (globally unknown in the late 19th century), a seemingly poor grasp of philosophy, and sexualized
pulpy content. Kaufmann also noted instances of clever wordplay in the English text that are impossible to express as such in the German language. Since the only copy of this alleged work is in English and there is not a single page of what would have been his original in German, opinion has been largely that the work is a forgery. Nevertheless, a minority hold the work to be authentic. In the mid-1980s, a handful of articles began to call for its reevaluation, including references to more recently discovered journals and letters from Nietzsche and Cosima Wagner. Amok Books' 1990 edition reprints many secondary articles and includes an original introduction calling for a reevaluation of the book. Nietzsche scholar Walter K. Stewart, in his 185-page monograph
Nietzsche: My Sister and I
— A Critical Study published in 2007, argues for the original's potential legitimacy by conducting a point-by-point analysis of Kaufmann's book review. In his 2011 follow-up,
Friedrich Nietzsche My Sister and I
: Investigation, Analysis, Interpretation, Stewart uses direct textual analysis to argue that whoever wrote
My Sister and I was intimate with every aspect of Nietzsche’s life and perspective. ==Editions==