April 10, 1901
Dr. Duncan MacDougall begins several experiments on humans and animals to measure a soul’s weight
MacDougall’s experiments on humans involved waiting patiently for nursing home patients to pass away naturally. As their time neared, the patients’ beds were placed on industrial scales and their weights carefully recorded before death and directly after death, with 6 patients being monitored by MacDougall and four other doctors.
The results were inconclusive at best, with one patient losing weight at death then gaining it back, 2 who lost weight at death then lost even more after a few minutes, and one lost 21.3 grams at the moment of death. The other two results were dismissed due to equipment issues.
MacDougall repeated the tests on dogs as well, attempting to prove animals did not have souls. He used 15 dogs, though could not find sick or dying animals; it’s presumed he poisoned healthy dogs to conduct his experiment. His reports indicated none of the dogs’ weights fluctuated after death.
Due to a small sample size, inaccurate measuring equipment, and questionable ethics regarding the dog testing, MacDougall’s “21 grams theory” has been criticized and is not considered scientifically sound. The theory has nonetheless found itself in popular culture, including 21 Grams (2003), The Empire of Corpses (2015), Gantz, Welcome to Night Vale, and Dark Matters: Twisted But True.