Buddhist practice is to make the manas accept that all dharmas are not the self

The existence of the manas and the tathāgatagarbha has no sequence of before and after; beginningless kalpas ago they existed simultaneously—naturally so, intrinsically so, with no rationale to be spoken of. Beginningless kalpas ago, because of the manas's ignorance, not understanding true reality, it arose with intent to grasp outwardly at objects, and thus the world of the five aggregates (pañcaskandha) came into birth, and all dharmas gradually came to be produced as well. Thereupon conflicts and disputes stirred without cease, and afflictions and suffering followed one after another without end. Cultivation is to make the manas accept that all dharmas are not the self; the mind consciousness must engage in contemplative practice (vipaśyanā-caryā) and deliberate that all dharmas are not the self. One must study and cultivate the principles of both the Greater and Lesser Vehicles, and only after learning them thoroughly can one, in the end, realize that all dharmas are not the self. All cultivation lays the foundation for this. Therefore, the heavier the mind of self, the further one is from liberation, and the more distant from becoming a Buddha. To subdue the self-nature of the manas is a heavy responsibility and a long road.