The Difference Between Insentient Things and Sentient Beings

Question: The four great elements—earth, water, fire, and wind—constitute all things with marks. Is the movement of the manas and consciousness also the function of wind? Do all insentient objects, such as cups, teapots, grass, and trees, also possess the tathāgatagarbha?

Answer: The movement of the manas and consciousness is itself the function of the nature of consciousness, because the mental factors (caittas) of the seven consciousnesses are operating. Wind cannot cause consciousness to move; it can only cause material objects to move. The four great elements of earth, water, fire, and wind can only constitute the six sense objects with marks—form, sound, smell, taste, touch, and dharmas—and cannot compose the formless mental dharmas. Insentient objects are not sustained by a single tathāgatagarbha operating alone; rather, it is through the sustaining and upholding function of the tathāgatagarbhas of sentient beings with common karma that insentient objects can exhibit the phenomena of arising, abiding, changing, and ceasing.

Because the three realms are mind-only, all dharmas lack inherent self-nature; they all come from the tathāgatagarbha, all are generated and sustained by the tathāgatagarbha, and thus no dharma can exist outside the tathāgatagarbha. The five-aggregate body born of the tathāgatagarbha is a sentient being, called a living being; it has a lifespan and vital activities, and killing it constitutes an offense. Conversely, that which lacks the functioning of the five aggregates is an insentient object; destroying it or consuming it does not incur the offense of killing, because material objects lack the vital activities of the five aggregates of form, feeling, perception, volitional formations, and consciousness.