Andrew Smart is the author of Autopilot: The Art and Science of Doing Nothing. A scientist and engineer interested in consciousness, brains and technology, his work traverses the boundaries of neuroscience, philosophy, culture, radical politics and metaphysics. He was raised in the U.S., educated and married in Sweden, lived in New York and Minneapolis and now lives in Switzerland.

After spending three days above 20,000 feet descending from the summit of the massive Himalayan peak Nanga Parbat with his brother Günther in June 1970, the famous mountaineer Reinhold Messner began experiencing the classic high-altitude hallucination: the appearance of a third phantom climber who was accompanying the pair on their descent.

Above an altitude of 6,000 meters without supplementary oxygen, mountaineers commonly experience hallucinations, bodily distortions, and visual or auditory pseudohallucinations. The hallucinations associated with severe hypoxia at extreme altitude mimic those found in schizophrenia. These same perceptions can also occur with hallucinogenic drugs such as LSD, mescaline, or psilocybin. Hallucinations are fascinating phenomena that have captivated human culture as far back as we know. During dreaming we are comfortable with people, landscapes, and things that do not really exist. However, if we see or hear these things while fully awake and are the only ones able to experience them, it is (at least in Western culture) alarming.

Schizophrenia exists universally, even though the experience of it is culturally specific. A recent anthropological study of schizophrenia revealed that people with schizophrenia in the United States have very negative relationships with their voices, while people in Africa and India report rather positive relationships with their voices. In India and Africa perhaps there is a bit more latitude regarding how we should perceive reality. Our Western epistemology dictates that things that do not conform to a rational explanation must be feared and controlled. Thus people with schizophrenia in the U.S. are much more tortured by the disease, not because of the condition, but because of the surrounding culture.

When the Virgin Mary heard an angel speak to her was she hallucinating? Socrates was convinced that a benevolent spirit called a daimon warned him when he was about to make a logical mistake. Joan of Arc was supposedly guided by the voices of various saints and even God, who helped her command the French army to defeat the British. Even Descartes is rumored to have heard voices. These voices came from behind and were so vivid to Descartes he was often convinced that he was being followed.

Andrew Smart is the author of Autopilot: The Art and Science of Doing Nothing. A scientist and engineer interested in consciousness, brains and technology, his work traverses the boundaries of neuroscience, philosophy, culture, radical politics and metaphysics. He was raised in the U.S., educated and married in Sweden, lived in New York and Minneapolis and now lives in Switzerland.

After spending three days above 20,000 feet descending from the summit of the massive Himalayan peak Nanga Parbat with his brother Günther in June 1970, the famous mountaineer Reinhold Messner began experiencing the classic high-altitude hallucination: the appearance of a third phantom climber who was accompanying the pair on their descent.

Above an altitude of 6,000 meters without supplementary oxygen, mountaineers commonly experience hallucinations, bodily distortions, and visual or auditory pseudohallucinations. The hallucinations associated with severe hypoxia at extreme altitude mimic those found in schizophrenia. These same perceptions can also occur with hallucinogenic drugs such as LSD, mescaline, or psilocybin. Hallucinations are fascinating phenomena that have captivated human culture as far back as we know. During dreaming we are comfortable with people, landscapes, and things that do not really exist. However, if we see or hear these things while fully awake and are the only ones able to experience them, it is (at least in Western culture) alarming.

Schizophrenia exists universally, even though the experience of it is culturally specific. A recent anthropological study of schizophrenia revealed that people with schizophrenia in the United States have very negative relationships with their voices, while people in Africa and India report rather positive relationships with their voices. In India and Africa perhaps there is a bit more latitude regarding how we should perceive reality. Our Western epistemology dictates that things that do not conform to a rational explanation must be feared and controlled. Thus people with schizophrenia in the U.S. are much more tortured by the disease, not because of the condition, but because of the surrounding culture.

When the Virgin Mary heard an angel speak to her was she hallucinating? Socrates was convinced that a benevolent spirit called a daimon warned him when he was about to make a logical mistake. Joan of Arc was supposedly guided by the voices of various saints and even God, who helped her command the French army to defeat the British. Even Descartes is rumored to have heard voices. These voices came from behind and were so vivid to Descartes he was often convinced that he was being followed.