The works of Friedrich Nietzsche provided a congenial philosophical mirror in which Rudolf Steiner often reflected on his own theory of ethical individualism. In Goethe’s morphology, on the other hand, Steiner saw a pioneering scientific methodology which provided a completely new way of understanding organic life, and hence a theoretical foundation for his own anthroposophy. The evolutionary theory of Ernst Haeckel also, and especially the theorem of biomorphic recapitulation (the ›biogenetic law‹), exerted an influence on Steiner that can hardly be overestimated. The three texts collected in this volume constitute therefore a valuable source for the study of Rudolf Steiner’s development, both in terms of his pre-theosophical work and with regard to the genesis of his esoteric writings.