Throughout history, many cultures have been fascinated by altered states of consciousness, whether in the form of dreams, hypnosis, hallucinations, trances, or visions. Such states may occur naturally, or may be induced by ritualistic activities or mind-altering substances. It has been hypothesized that some of the earliest art ever created by humans—such as the cave paintings in Lascaux—relate to visions induced by ritualistic dancing. In the 20th century, Sigmund Freud’s foundational text for psychoanalysis, The Interpretation of Dreams (1900), sought to systematize the mysteries of dream symbolism, proving hugely influential to artists interested in the subconscious, such as the Surrealists. More recently, in an iconic early performance titled Rhythm 2 (1974), Marina Abramović ingested a mind-altering prescription drug in front of an audience as an attempt to explore the relationship between the mind and the body.