Short answers, pulled from the story.
Duncan MacDougall reported that the soul lost exactly 21 grams when the last breath left the body. This measurement was recorded on a massive industrial scale during experiments conducted in the year 1901 in Haverhill, Massachusetts.
Plato divided the soul into three parts: the rational mind located in the head, the spirited emotion in the chest, and the appetitive desire in the stomach. This tripartite structure mirrored the class structure of an ideal state and reflected his view of the soul as an immortal, immaterial substance.
The Buddhist doctrine of anatta, or not-self, posits that what we call a self is merely a temporary collection of five aggregates: form, sensation, perception, mental formations, and consciousness. The Buddha refused to answer whether the soul existed as a distinct entity, teaching instead that all components are impermanent and empty of essence.
The Quran distinguishes between the ruh, or spirit, which is the divine breath of life, and the nafs, or self, which encompasses the ego, desires, and the capacity for evil. Al-Ghazali described the soul as a spiritual substance containing animal, devilish, and angelic inclinations that create a psychological landscape for moral choice.
Thomas Aquinas argued that the soul is the first actuality of the living body but can exist without the body after death. He asserted that the soul is entirely in the whole body and entirely in every part of it, rejecting the notion that it resides solely in the heart or brain.
In Taoism, the soul is divided into two distinct components: the hun, or ethereal soul, which is associated with light and the mind and departs the body after death, and the po, or corporeal soul, which is tied to the body and instincts and dissolves back into the earth.