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What a man thinks that he is: This is the old secret. The mind, it is said, is of two kinds,

pure and impure; impure from the contact with lust, pure when free from lust.

Mind alone is the cause of bondage and liberty for men; if attached to the world,

it becomes bound; if free from the world, that is liberty.
Maitrayana
Brahmana-Upanishad (more…)