21 gram Experiment

The 21-gram experiment is a popular study conducted in 1901 and published later in 1907 by Duncan MacDougall, a physician from Haverhill, Massachusetts. He wanted scientifically to determine if the soul has some physical mass or weight. So he conducted his experiment in 1901 with 6 patients whose death was imminent.

Experiment 

He chose  6 patients in a nursing home who were close to death. Out of those six-four were suffering from tuberculosis, one from diabetes, and one from one unidentified causes. All chosen patients were suffering from illnesses which caused physical exhaustion because he needed that patients remain still when they die so that he can major them accurately.

When the patients were close to death, their whole bed was placed on an industrial-sized scale that can handle within two-tenths of an ounce.

Outcome

MacDougall disregarded the results of two patients, one patient result disregarded on the grounds that scales were "not finely adjusted", and results of another patient was not measured as the patient died while the equipment was still being calibrated.

Out of the remaining four samples, two bodies lose weight during death but lost even more weight after some time. One patient lost weight but then put the weight back on. Only one out of six patients lost 21.3 gram( three-fourth of an ounce).

Later MacDougall conducted the same experiment with 15 dogs to prove that only the human soul has weight. Out of those 15 samples, no dog loses weight.

Before he could publish his research officially 

The New York Times published the story in an article titled "Soul has Weight, Physician Thinks" in 1907. During the same year, but the official report on the study gets published. MacDougall believed that his experiment proved that the human soul might have weight.

Why other scientist rejected this experiment 

Fraternity of scientist rejected this experiment on many bases few reasons for rejection are as follow

1.Sample Size- according to scientists Sample size is not enough, experiment was conducted only on 6 people which is far less than accepted ratio, even from those 6 people only one body showed sign.

2.Experiment was not repeated- MacDougall himself said that to believe this theory this experiment should be repeated many times, only then experiment will be successful 

3.Flawed Methods- Many scientists criticised him for the weak techniques and equipment he used for the experiment. Many scientists claimed that this experiment was the case of selective reporting.

4.Human vs Dog- He claimed that he finds out dog Soul doesn't have weight but human Soul might have weight, but other scientists claimed that this difference in weight fluctuation was because of the sweat gland dogs don't have sweat glands so their weight remains the same. But when human die scientist 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 leads to weight loss.

21-gram experiment and It's acceptance in masses 

Although scientists had rejected MacDougall's claim somehow this experiment became immensely popular among masses due to this experiment the people believe that soul has some physical weight , and popular culture played a major role in hyping this experiment more, the concept of 21-gram weight of soul had been discussed in many movies and songs.