The Difference Between Intellectual Understanding and Realized Awakening Is Vast

This knowing is primarily the knowing of the mind consciousness, though behind it there is also the knowing of the manas. The knowing of enlightenment is a knowing of the nature of wisdom, different from the knowing before enlightenment. Before enlightenment, the mind consciousness merely speculates about the tathāgatagarbha, the manas does not know the true reality of the dharmadhātu, and it takes the five aggregates as the self—thus neither consciousness possesses wisdom. After enlightenment, the mind consciousness has realized the tathāgatagarbha, and the manas has come to know the true reality of the dharmadhātu; this wisdom is then extraordinary. Afflictions will gradually fall away, ignorance will gradually diminish, self-grasping will become lighter and lighter, and ultimately one can transform the consciousnesses into wisdom. Therefore, in genuine enlightenment the manas must also attain enlightenment; otherwise, the manas would lack the wisdom of realization, could not eliminate afflictions, and could not transform the consciousnesses into wisdom. 

After enlightenment, only realization brings knowing—words cannot express it thoroughly. It is like a person who has eaten honey: only he himself knows its sweetness completely in his own mind. No matter how he describes it to others, others can merely understand it intellectually, but cannot truly and vividly experience it, because they have not tasted it themselves, not personally felt it. Therefore, the intellectual understanding of the tathāgatagarbha arrived at through the mind consciousness's speculation, and the realized enlightenment of the tathāgatagarbha personally attained by the manas, differ enormously in wisdom and enormously in their benefits; the subsequent cultivation is as different as heaven and earth.