More than 100 years ago, an American doctor conducted a strange study measuring the weight of the human soul.
An eternal soul is a powerful concept. Many religions consider it a core belief, and many people find solace in the idea of the soul when facing loss.
This may be why some individuals are not content to associate the soul solely with faith; they seek scientific explanations to prove the soul’s existence. If you have ever heard that the soul weighs 21 grams, it’s not just a fact from movies or stories; it stems from one of the rather peculiar experiments.
So, how much does the soul actually weigh? The truth is that science has yet to prove the existence of the soul, and scientists have not been able to weigh it, but the story of a doctor who took the effort to weigh the soul is certainly worth our attention.
This unique experiment was conducted on six patients who had died. These patients were placed on special Fairbanks industrial scales before they passed away. Dr. MacDougall intended to weigh each individual’s body before and after their death to determine any weight changes measured by this highly accurate scale. The patients selected were all in a dying state, consisting of five men and one woman, two of whom had tuberculosis.
Fairbanks Scale
Along with four other doctors, Dr. MacDougall carefully measured the patients’ weights before they passed away. When they took their last breaths, an interesting event occurred.
“Suddenly, right after death, the scale needle dropped sharply and showed no signs of rising again. The weight lost was about ¾ ounce (approximately 21 grams)” – Dr. MacDougall wrote.
The experiment was carried out on the next patient and yielded similar results. Dr. MacDougall noted that he had discovered something extraordinary. A piece in the New York Times on March 11, 1907, recorded this historic moment: “When life ceased, the scale needle suddenly dropped, and the result was remarkable; it seemed that something had just separated from the body. Immediately, the usual weight loss after death was calculated, but we were still missing 1 ounce.”
Dr. Duncan MacDougall
All five doctors conducted measurements and compared their results. Not all patients lost the same body weight upon death, but a weight loss was observed. Unfortunately, results could only be recorded from four patients due to technical errors; two patients passed away before the doctors could set up the equipment.
So, what accounted for the weight loss? The doctors calculated all possible losses, such as air in the lungs or bodily fluids, but could not explain the missing 1 ounce. In the case of the third patient, there was an interesting change; the body weight did not change immediately after death, but one minute later, the weight dropped by 1 ounce. Dr. MacDougal explained this difference as follows:
“I believe that in this case, the man’s soul remained suspended in the body for one minute after death before it was freed. There is no way to calculate it; I think the difference is due to the differing temperament of each person.”
After the experiments and consultations with the other participating doctors, it was determined that the average weight loss for each person was ¾ ounce. Dr. MacDougall concluded that the human soul weighs 21 grams.
Dr. MacDougall conducted similar experiments on 15 dogs. The experiments showed no change in weight after they died. MacDougall concluded that this could indicate that only humans possess a soul.
Does the soul really weigh 21 grams?
H. LAV. Twining, a physics teacher at Los Angeles Polytechnic High School, attempted to conduct a similar experiment on mice in 1917. His conclusions aligned with Dr. MacDougall’s findings, showing no weight deviation when the mice died.
Dr. MacDougall was a respected physician in Haverhill and led the research association in this field for six years before the official experiment. Although this experiment is considered unethical by modern standards, it remains a unique study that has attracted much criticism from various religions.
Dr. MacDougall acknowledged the need for further research to verify the results. However, after these experiments, he shifted his focus to researching the possibility of capturing images of the soul via camera at the moment of death. Unfortunately, the doctor’s career did not yield any additional notable achievements following the soul weight experiment. Dr. Duncan MacDougall passed away in 1920.
Unanswered Questions
Dr. MacDougall’s study had a very small sample size; therefore, even at that time, many people were skeptical of his results. He himself acknowledged that more experiments were needed to confirm whether the soul has mass. However, no one conducted further experiments, partly due to ethical reasons and partly because these experiments seemed rather bizarre.
In the early 2000s, a farmer in Oregon attempted to replicate the soul-weighing experiments with 12 sheep and found that most of their weights increased by 30 to 200 grams but returned to normal just a few seconds later. This incident was recorded in Mary Roach’s book “Spook: Science Tackles the Afterlife”, published in 2005.
The author of the book also mentioned that Dr. Gerry Nahum, a chemical engineer and physician at Duke University Medical School, had developed a hypothesis that the soul, or at least consciousness, must be associated with information, which corresponds to a certain amount of energy. Since the equation E = mc² states that energy equals mass multiplied by the speed of light squared (Einstein’s formula), this energy could essentially be weighed with sufficiently sensitive electromagnetic equipment. As of 2007, Dr. Nahum had not received funding for experiments to prove his assertion correct or incorrect.
In short, science has yet to determine the weight of the soul or whether the soul exists, leaving the opportunity for explanation to religious faith.
