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The Rudolf Steiner Archive

a project of Steiner Online Library, a public charity

The Essence of Anthroposophy
GA 80a

1. The Difference Between Calculation and Operation 19 October 1904
2. Ellipse, Hyperbola, Lemniscate, Circle 26 October 1904
3. Trigonometry 4 November 1904
4. Sine, Cosine, Tangent, Cotangent 9 November 1904
5. The Fourth Dimension I 21 August 1906
6. TThe Fourth Dimension II 23 August 1906
7. The Fourth Dimension III 25August 1906
8. The Fourth Dimension IV 27 August 1906
9. Christ And Luzifer 31 August 1906
10. The Molten Sea 7 August 1905
11. The Interconnection Between the Three Worlds and the Natural World 8 August 1905
12. The Descent of Man 9 August 1905
13. Light on the Path I 10 August 1905