Frierich Wilhelm Nietzsche (October 15, 1844 – August 25, 1900) (IPA: [ˈfʁiːdʁɪç ˈvɪlhəlm ˈniːtsʃə]) was a nineteenth-century German philosopher and philologist. He wrote critical texts on religion, morality, contemporary culture, philosophy, and science, using a distinctive German language style and displaying a fondness for aphorism. Nietzsche's influence remains substantial within and beyond philosophy, notably in existentialism and postmodernism. His style and radical questioning of the value and objectivity of truth raise considerable problems of interpretation, generating an extensive secondary literature in both continental and analytic philosophy. Nonetheless, his key ideas include interpreting tragedy as an affirmation of life, an eternal recurrence (which numerous commentators have re-interpreted), a rejection of Platonism, and a repudiation of (especially 19th-century) Christianity.