This series of lectures is an introductory, but not elementary, course into the anthroposophical worldview. It shows how basic anthroposophical concepts are constructed and what way of thinking is characteristic of modern spiritual science. Considering the interaction between man and nature, Rudolf Steiner comes to the conclusion that both the appearance of man and his essence come from the extraterrestrial, non-physical world. Steiner shows how, by strengthening one’s thinking, one can achieve further degrees of knowledge of reality. Analyzing unusual perspectives of human life in the contradictions between the events of waking life and dreams, dreams and memories, memories and what has escaped memory, and supplementing these considerations with the experience of supersensory knowledge, Author paints pictures of a person’s passage not only of earthly life, but also of the spiritual worlds. Clear logical constructions step by step introduce the reader to the system of concepts of anthroposophy – the initiatory science of our time.