The anthroposophy of Rudolf Steiner is not a theoretical system, but the results of research based on direct observation. As Steiner's research was so vast and conducted over such a long period of time, no single book can be said to contain the whole of his spiritual teaching. However, of all his books on occult science, also known as esoteric science, come closest. Steiner even referred to it as 'an epitome of anthroposophical spiritual science'.
