Remaining Mass

In 1907, Dr. Duncan MacDougall attempted to determine the weight of the human "soul" by measuring the change in a body's mass at the moment of death. He concocted an experiment on six patients who were about to die by placing their death beds on a highly sensitive scale, and was able to collect data for four of them. He determined that there was a loss of twenty-one grams (21g) within a minute of each patient drawing his or her final breath. He repeated the process with several dogs and determined that there was no similar drop in mass associated with their deaths, which is to be expected if only humans have massive souls.

A fierce debate raged over how to interpret these results, whether the experiment was truly measuring something significant, or if it was a phenomenon easily explained by the shut-down of life processes interacting with the external environment, or if it was an insignificant statistical anomaly. The experiment has apparently not been repeated with humans.

What is known with certainty is that the mass of human remains does decrease with time, as the body dries and decomposes, giving off its gaseous stench, and leaching foul liquid, until after a sufficiently long period of time, its remains are no longer distinct from its environs.7