The Schiller File: Supplements to the Collected Works of Rudolf Steiner"Concerning: Electricity, Terrestrial Magnetism, Radio Conduction of Heat, Sensitive Flames, Etheric Formative Forces, The Four Ethers, Resonant Oscillation, Refinement of Peat Fibers, etc." Anthroposophy has manifold roots in natural science. Rudolf Steiner never tired of saying that the development of scientific awareness had given people the possibility of freedom, that the way to cognizing the spiritual world is based on the natural scientific