Legend has it that a person's soul weighs 21 grams. Is there any truth to it?
An everlasting soul is a powerful concept; it's the central feature of many religions and a deeply comforting belief in the face of loss.
The story starts at the turn of the last century in Dorchester, a neighborhood in Boston. A reputable physician named Duncan MacDougall had a bee in his bonnet: If humans had souls, he thought, those souls must take up space. And if souls take up space, well, they must weigh something — right? MacDougall's first patient, a man, died on April 10, 1901, with a sudden drop in the scale of 0.75 ounce . And in that moment, the legend was born. It didn't matter much that MacDougall's next patient lost 0.5 ounce 15 minutes after he stopped breathing, or that his third case showed an inexplicable two-step loss of 0.5 ounce and then 1 ounce a minute later.