Nietzsche contra Wagner; Out of the Files of a Psychologist is a critical essay by Friedrich Nietzsche, composed of selections he chose from among his earlier works. The selections are assembled in this essay in order to focus on Nietzsche's thoughts about the composer Richard Wagner. As he says in the preface, when the selections are read "one after the other they will leave no doubt either about Richard Wagner or about myself: we are antipodes." He also describes it as "an essay for psychologists, but not for Germans". It was written in his last year of lucidity (1888–1889), and published by C. G. Naumann in Leipzig in 1889. Nietzsche describes in this short work why he parted ways with his one-time idol and friend, Richard Wagner. Nietzsche attacks Wagner's views, expressing disappointment and frustration in Wagner's life choices (such as Nietzsche's mistaken belief that Wagner had converted to Christianity, perceived as a sign of weakness). Nietzsche evaluates Wagner's philosophy on tonality, music and art; he admires Wagner's power to emote and express himself, but largely disdains what the philosopher deems his religious biases.