Paul Sedir (born Yvon Le Loup; 2 January 1871 - 3 February 1926) was a French author, professor, banker, and mystic noted for his extensive work on esotericism and Christian mysticism. A student of Gerard Anaclet Vincent Encausse, better known as Papus, founder of the Martinist Order, into which Sedir was initiated. Sedir's first text, Les Miroirs Magiques (Magic Mirrors), was published in 1894 by Lucien Chamuel. This work, along with others like Les Temperaments et la Culture psychique (1894), Les Incantations (1897), and La Medecine occulte (1900), reflects his profound knowledge in various domains of esotericism, including Kabbalah, astral light, and magical practices.

In this collection of two of Sedir's works, Austin Avison introduces Paul Sedir, situating him in the exciting period of societal and cultural changes during the pre-war years in Europe. Avison then offers a translation of Sedir's Dreams: Theories-Practice-Interpretation, a short discourse of how dreams function, their art, and a list of dream interpretations, and finally his translation of Magic Letters, which offers an insight into Sedir himself not only through his own prologue, but also in the collection of letters he curated for the collection. These two texts, along with Sedir's other contributions, marked a significant chapter in the development of French esotericism in the early 20th century.