This anonymously-written book on the principles of 'Hermetic Philosophy' has had an enduring impact on many branches of esotericism since its first publication in 1908. Spare and concise in its language, it contains a detailed exegesis of 'The Kybalion', an apparently secret manuscript of initiation (no copy of which has ever been published). The book sets out the seven universal principles underlying all existence, and gives 'keys' to the disciplines required to achieve mastery of the Hermetic Art.