Is the Seed Substantially Existent?

Only the Tathāgatagarbha is truly and substantially existent. The Seven Fundamental Seeds are the intrinsic seeds of the Tathāgatagarbha; they have never undergone birth or cessation, possess the real function of giving rise to all phenomena, and can thus be said to be substantially existent. As for karmic seeds, they are generated subsequently, subject to birth, cessation, and transformation, and are therefore not substantially existent. Although Buddha-nature is also unborn and unceasing, it ceases to function in the Nirvana without Remainder, so it cannot be considered completely substantial. In the Nirvana without Remainder, the Seven Fundamental Seeds still remain, while Buddha-nature does not. The Seven Fundamental Seeds are like the heart of the Tathāgatagarbha, coexisting with it, and can therefore be regarded as substantially existent. All else is insubstantial.