The Birth of Tragedy (1872) was Nietzsche's first book, The Geneology of Morals (1887) one of his last. Though they span the career of this controversial genius, both address the problems such as the conflict between the moral versus aesthetic approaches to life, the effect of Christianity on human values, the meaning of science, and the famous dichotomy between the Apollonian and Dionysian spirits, among many themes which Nietzsche struggled throughout his tortured life.