The first volume of Welt- und Lebensanschauungen im neunzehnten Jahrhundert appears; the second follows one year later. Revised and expanded, this work appears in 1914 under the title, The Riddles of Philosophy.
Lectures in the Theosophical Library on Goethe’s Fairy Tale and Nietsche. In autumn, he begins a lecture cycle on mysticism.
First encounter with Marie von Sivers, who becomes his closest colleague from 1902 onward. She had trained in the art of recitation at a Paris conservatory and in Dramatic Art in St. Petersburg. She is translator of several works by Edouard Schuré.
Mysticism in Modern Thought appears. His second lecture cycle held in the Theosophical Library in 1901/02 also appears, adapted to book form, under the title, Christianity as a Mystical Fact.
Steiner becomes a member of the Theosophical Society and General Secretary of the German Section of the Theosophical Society from October 1902 onward.
Encounter with Annie Besant.
Teaches at an independent college founded by the Friedrichshageners Bruno Wille and Wilhelm Bölsche.