This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
The Katha Upanishad opens with an act of casual cruelty. Vajashravasa, performing a sacrifice meant to give away everything he owns, gives only his old and useless cattle, and when his son Nachiketas asks pointedly whom his father will give him to, the irritated answer is Death. The father's slip of the tongue becomes the boy's literal errand: Nachiketas travels to Death's own house and waits three days at the door before Yama, embarrassed at having kept a guest waiting unfed, offers him three boons in apology.
Nachiketas spends the first two on his father's peace of mind and on a sacrificial fire, but the third boon is the one the whole text exists to answer: what becomes of a person after death, does the self go on or not. Yama tries everything to talk him out of the question, offering sons, cattle, elephants, gold, a long life and rule over a kingdom instead, and Nachiketas refuses every substitute, pointing out that riches never satisfy for long and that a boy who has already met Death is not going to be distracted by them.
Yama's eventual answer is the philosophical core of the text: the self is never born and never dies, it is not slain when the body is slain, and it cannot be reached by clever argument or wide learning, only by a mind made still enough to receive a teacher's grace. The lesson arrives through image as much as statement, most memorably the simile of a chariot, in which the body is the chariot, the intellect the driver, the mind the reins and the senses the horses, all needing careful, disciplined handling to reach the road's end. Read as a whole, the Upanishad is less a treatise than the record of one boy's refusal to accept an easy answer, and Yama's eventual respect for exactly that refusal.