In the early 20th century, physician Duncan MacDougall tried to prove the existence of the soul in Massachusetts. The strange method needed people on the brink of death and some dogs.

First of all, the Scottish doctor believed that the soul had physical mass and, therefore, it was possible to weigh it. His decision, then, was to measure some people just before death and, after death, to measure them again. The difference in weights would be the weight of the soul.

Thus MacDougall sought out patients in the final stages. These patients were weighed in his experiment until after they were disembodied their 'ghosts' were weighed as well. The terminal patients had tuberculosis or similar diseases, so they were usually exhausted and immobile at the time of measurement.

Duncan MacDougall (Public Domain)

Scottish doctor's strange method

The doctor built large scales on the bed in his office for his patients. One version of events points out that they had their body openings blocked. Due to Mac Dougall's scientific rigor, the goal would be to not let any fluid escape the body and impact the body weighing.

New York Times article from 1907. (Credit: Wikimedia Commons)

But at the time of the weighing, things did not go as planned. Apparently, there was much questioning of the doctor's experiment and, as he wrote, "interference from people who oppose our work.

Supposedly, many complained about the fact that the doctor was weighing patients as they died instead of providing care and treatment to them. Especially since some died while he was adjusting his scales.

As for the results with humans, one patient seems to have lost weight at the exact moment of death and another lost 14 grams before death was confirmed. Afterwards, he was found to have lost 42.5 grams. Consequently, a third also lost weight soon after his death.

Obviously, most would find this a finding of some bad scales, but MacDougall concluded it as proof of the existence of the soul.

Control experiment

Surely, this story could get worse. The doctor, as a "scientific weigher" of spirits, realized the need to do a control experiment.

So he killed 15 healthy dogs, even figuring that dogs have no souls to lose, so they wouldn't get lighter upon death. As suggested, the animals did not lose weight according to their scales. MacDougall published his results which were instantly repelled.

In conclusion, the methodology and ascertainment were flawed from the beginning of the experiment. The doctor himself admitted that it was difficult to measure the exact time of death.

In addition, any weight changes collected in their small samples of patients could be attributed to a few basic factors. As examples, the sudden increase in sweating and evaporation of moisture happen when body temperature rises right after death because blood no longer cools while circulating.

Meanwhile, dogs sweat through their paws, so any weight loss would be minimal. All these reasons led him to be ridiculed by his colleagues for a long time.

In other words, he didn't prove the existence of the soul and still became a dog killer.