Abstract of Nirvana Sutra - Chapter 43

"Oh good man! Ignorance is the root of all defilements. Why? All beings, due to the causal relations of ignorance, call forth all imaginings and forms in the fields of the five skandhas, the 12 spheres, and the 18 realms [of senses]. These are inverted notions as regards image, mind, and worldview. From these, all the defilements arise. Therefore, I state in the 12 types of sutras: 'Ignorance is the cause of greed, the cause of ill-will, and the cause of (own) ignorance'. "

Read more in Nirvana Sutra, Chapter 43 - On the Bodhisattva Kasyapa 4.
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