Is there a measurable “light of life”? This episode dives into the strange history of the 21 grams experiment—the infamous claim that the soul has weight—and contrasts it with modern research into biophotons, the faint light emitted by all living organisms. We’ll explore how ultra-weak photon emission (UPE) arises from cellular metabolism, what it might reveal about oxidative stress and disease, and whether this ghostly glow could one day become a powerful tool for non-invasive diagnosis. From pseudoscience to cutting-edge biology, we trace the line between myth, mystery, and measurable science.