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
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