An Outline of Occult Science is a book by Rudolf Steiner, an Austrian philosopher, and esotericist. Published in 1913, the book explores various aspects of occult science, including spiritual development, the nature of the human being, and the evolution of the cosmos. Steiner presents a comprehensive overview of esoteric knowledge, drawing from his experiences and insights. He delves into topics such as the existence of higher spiritual beings, the nature of karma and reincarnation, and the connection between the physical and spiritual worlds.