The knowing of the tathāgatagarbha and the knowing of the manas are completely different in content. For example, when the manas realizes the tathāgatagarbha and knows the tathāgatagarbha, the tathāgatagarbha cannot realize itself and does not know itself. When the manas realizes that the physical body is neither self nor real, the tathāgatagarbha cannot know that the physical body is not real and is not the tathāgatagarbha itself. The content contemplated by the tathāgatagarbha's volitional mental factor (cetasika) is completely different from the content contemplated by the manas's volitional mental factor; the difference is vast. Therefore, the dharmas realized by the manas cannot be realized by the tathāgatagarbha, and the decisions and resolutions made by the manas cannot be made in the same way by the tathāgatagarbha—the tathāgatagarbha merely cooperates with and accords to the manas's decisions.
When the manas investigates a dharma, the tathāgatagarbha does not know when the investigation will bear fruit, but the tathāgatagarbha can discern the manas's volitional mental factor, discern conditions and karmic seeds, and mainly provides the seeds of consciousness that the manas needs, cooperating with the manas's deliberation and investigation. As for the specific matters of phenomenal events, the tathāgatagarbha does not know them at all. This is the distinction between the tathāgatagarbha and the seven consciousnesses.
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