This doubt that arises, consequent on the death of a man - some saying, “It exists” and others saying, “It does not exist” - I would know this, under your instruction. Of all the boons, this one is the third boon.(Ka. Up. 1.i.20)
Naciketa, in the crisis evoked by the curse of his father, asks Death (Yama) whether our post mortem fate is continuance or annihilation? Being born is being given to death. Is that all there is?
The answer he receives is that it is better not to ask that question. Only the renounced individual is fit to pursue this, it being far easier to gain wealth and delightful nymphs. Knowledge such as this can only be imparted by a realised teacher and not through philosophic lucubrations.
The Self is not certainly adequately known when spoken of by an inferior person; for It is thought of variously. When taught by one who has become identified with It, there is no further cogitation with regard to It. For It is beyond argumentation, being subtler even than the atomic quantity.(Ka. 1.ii.8, 9)
The wisdom that you have, O dearest one, which leads to sound knowledge when imparted only by someone else (other than the logician) is not to be attained through argumentation. You are, O compassionable one, endowed with true resolution. May our questioner be like you, O Naciketa
A large powerful magnet will magnetize a small piece of iron. Vedantic tradition emphasizes the ideal of a living Master.