21 граммдық эксперимент: Рудың салмағы туралы зерттеу

1907 scientific study by Duncan MacDougall

The 21 grams experiment refers to a pseudoscientific study published in 1907 by Duncan MacDougall, a physician from Haverhill, Massachusetts. MacDougall hypothesized that souls have physical weight, and attempted to measure the mass lost by a human when the soul departed the body. MacDougall attempted to measure the mass change of six patients at the moment of death. One of the six subjects lost three quarters of an ounce (21.3 grams). MacDougall stated his experiment would have to be repeated many times before any conclusion could be obtained. The experiment is widely regarded as flawed and unscientific due to the small sample size, the methods used, as well as the fact only one of the six subjects met the hypothesis. On the belief that humans have souls and that animals do not, MacDougall later measured the changes in weight from fifteen dogs after death. MacDougall said he wished to use dogs that were sick or dying for his experiment, though was unable to find any. It is therefore presumed he poisoned healthy dogs. MacDougall's results were published in April of the same year in the Journal of the American Society for Psychical Research, and the medical journal American Medicine.

Following the publication of the experiment in American Medicine, physician Augustus P. Clarke criticized the experiment's validity. Clarke noted that at the time of death there is a sudden rise in body temperature as the lungs are no longer cooling blood, causing a subsequent rise in sweating which could easily account for MacDougall's missing 21 grams. Clarke also pointed out that, as dogs do not have sweat glands, they would not lose weight in this manner after death. and psychologist Bruce Hood wrote that "because the weight loss was not reliable or replicable, his findings were unscientific". Professor Richard Wiseman said that within the scientific community, the experiment is confined to a "large pile of scientific curiosities labelled 'almost certainly not true'".

In 1911, The New York Times reported that MacDougall was hoping to run experiments to take photos of souls, but he appears to not have continued any further research into the area and died in 1920. In 2009, Hollander Jr.'s experiment was subjected to critical review by Masayoshi Ishida in the same journal. Ishida found Hollander's statement of a transient gain of weight was "not an appropriate expression of the experimental result", though he admitted "the cause of the force event remains to be explained". He also warned about possible malfunctions of the weighing platform in two of the cases. Similarly inspired by MacDougall's research, physician Gerard Nahum proposed in 2005 a follow up experiment, based on utilizing an array of electromagnetic detectors to try to pick up any type of escaping energy at the moment of death. He offered to sell his idea to engineering, physics, and philosophy departments at Yale, Stanford, and Duke University, as well as the Catholic Church, but he was rejected.

Despite its rejection as scientific fact, MacDougall's experiment popularized the idea that the soul has weight, and specifically that it weighs 21 grams. a 2013 podcast of Welcome to Night Vale, the 2015 film The Empire of Corpses a 2021 episode of Ted Lasso, and a 2023 issue of the manga One Piece. Songs entitled "21 Grams" which reference the weight of a soul have been released by Looptroop Rockers (2005), Niykee Heaton (2015), Fedez (2015), August Burns Red (2015), Thundamentals (2017) and Arena (2022). In 2024, German musicians KLAN and Madeline Juno released "21 Gramm". Travis Scott references the concept in the 2018 song "No Bystanders". MacDougall and his experiments are explicitly mentioned in the 1978 documentary film Beyond and Back, and episode five of the first season of Dark Matters: Twisted But True. A fictional American scientist named "Mr. MacDougall" appears in Gail Carriger's 2009 novel Soulless, as an expert in the weight and measurement of souls.