The Doors of Perception is Aldous Huxley's groundbreaking 1954 essay that explores his experiences with the psychedelic substance mescaline. In the book, Huxley recounts a controlled experiment in which he took mescaline and recorded his thoughts, visions, and philosophical insights during the altered state of consciousness. The work delves into the nature of human perception, consciousness, and reality, suggesting that the mind is filtered by the brain and that psychedelic substances can "open the doors" to a more profound, unfiltered awareness. Huxley draws from art, religion, psychology, and mysticism to interpret the experience, making the book a foundational text in both psychedelic literature and 20th-century philosophy.