The Katha - upanishad, through the story of Nachiketa, discussed death and the permanence of the soul (Atman).

卡塔奥义书，通过尼兹卡塔的故事，论述了死亡与灵魂(生命的本源，自我)的持久性。

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Unlike other well documented forms of storytelling through song in Tamil Nadu - like the Katha Kalakshepam from Thanjavur - Kathaiyum Paattum is a more informal art performed, as experts say, "under the radar".

BBC: Is Indian storytelling a dying art?