Some may suspect that nothing could be further from practical thinking than a spiritual science aspiring to be anthroposophical, which consciously sets out to explore the supersensible in humanity and nature. However, upon becoming acquainted with Rudolf Steiner's discussions on the practical training of thought, one might even feel confirmed in their beliefs. This is strange, yet also exciting: if one engages with the concrete exercises described by Rudolf Steiner, initial skepticism gives way to a growing astonishment and trust in the correctness of the chosen path. Thinking aligns itself with its object, thereby providing increasingly precise insights into the essential and guiding actions through further ideas. In the winter semester of 1908/1909, Rudolf Steiner delivered four lectures on the practical training of thought.