Myth busting about soul's weight

Krishna: There is no evidence of soul, according to science.

Soul?! What is it according to science and scientists?

One silly ‘scientist’ did some work ages back that led to this wrong notion. The origin of the 21g figure can be traced to Duncan MacDougall, a doctor working in Haverhill, Massachusetts in the early 1900s.

MacDougall (1) had a keen fascination with death and spent part of his career on an almost obsessive hunt for evidence of the soul. He thought that if humans had a soul, it must exist in the body as some kind of material. And that material must weigh something.

MacDougall set out to test his theory with what was an excruciatingly bad experiment. In 1907, the year Einstein applied the laws of gravity to his special theory of relativity, MacDougall published his findings in American Medicine.

MacDougall's paper reveals as much about the author as it does about the quality of work that could get into medical journals at the time. MacDougall describes how he set about converting a hospital bed into a rudimentary balance so he could measure a patient's weight change as they died. The bed balance was sensitive, so to prevent his soon-to-be-dead patients from messing up his data, MacDougall hunted around for people who were dying of tuberculosis. As he noted: "It seemed to me best to select a patient dying with a disease that produces great exhaustion, the death occurring with little or no muscular movement, because in such a case, the beam could be kept more perfectly at balance and any loss occurring readily noted." In other words, there was to be no flailing around that could upset the scales.

In all, MacDougall managed to recruit a mere six dying people for his study, four of whom had tuberculosis. In turn, each was tucked up in his modified bed and their weight monitored until some minutes after their death. Any bowel movements or urination at death were fine, at least so far as the experiment was concerned, as it all stayed on the bed.

With a nod to best scientific practice, MacDougall then repeated the study with 15 dogs, which according to his religious beliefs, were not blessed with souls. It's not clear how MacDougall managed to get his dogs to die without rocking the bed, but some scientists suspect a nasty cocktail of drugs was used.

At the end of his foray into science, MacDougall declared that humans lost up to three-fourths of an ounce upon death, a figure that doesn't have quite the same ring as 21g, the metric equivalent. The dogs, he said, lost nothing. What else might it be if not the weight of the soul departing, he asked.

But now we know why the weight loss occurs.

Actually it is the gases that escape that caused this weight loss in the experiments.

Dead bodies lose a lot of weight over time because minute, intercellular structures called lysosomes release enzymes that break the body down into gases and liquid.

Footnotes:

1. Is there lightness after death?