In 1907, a Massachusetts doctor named Duncan MacDougall performed an unusual series of experiments. Intrigued by the idea that the human soul had mass, and could therefore be weighed, Dr. MacDougall put together a bed fitted with a sensitive set of beam scales, and convinced a series of terminally ill patients to lie on it during the final moments of their lives.
MacDougall was nothing if not detail-oriented: He recorded not only each patient’s exact time of death, but also his or her total time on the bed, as well as any changes in weight that occurred around the moment of expiration. He even factored losses of bodily fluids like sweat and urine, and gases like oxygen and nitrogen, into his calculations. His conclusion was that the human soul weighed three-fourths of an ounce, or 21 grams.
It’s hard to imagine these experiments getting any serious attention from the scientific community today. But the lines of thinking that led to them — and the reactions they generated — remain with us to this day.
