Lecture Notes on the Sūtra of the Collection of the Father and Son (Twenty)

The Arising and Ceasing of the External Earth Element

When the external earth element gradually formed, it took twenty small kalpas—336 million years—to be established from empty space that originally contained nothing, gradually forming the universe of the inanimate world of the trichiliocosm (three-thousandfold great world system). After the trichiliocosm is destroyed, there is again nothing at all; everything subject to arising and ceasing is empty, without a single dharma.

The seed of the earth element exists within the tathāgatagarbha, and the seed itself is formless and markless—it is empty. The external mountains, rivers, and great earth that it forms are also empty in their self-nature, lacking any inherent self-existence; they cannot determine their own existence, but are transformed and fabricated by the tathāgatagarbha. The hardness of material objects is likewise empty, formless and markless, arising and ceasing along with the objects themselves.