The Origin of External and Internal Divisions of Marks

Question: Are the television, tables, chairs, and benches in my room manifested solely by my own Tathāgatagarbha, or are they co-manifested by the Tathāgatagarbha of all sentient beings?

Answer: All external phenomena are collectively manifested by the Tathāgatagarbha of sentient beings sharing collective karma. The Tathāgatagarbha of a single sentient being cannot independently manifest any external object. This is because in any given living environment, there is never just one sentient being alone, but countless sentient beings coexisting. These environments belong to beings sharing collective karma. Therefore, the Tathāgatagarbha of these beings, based on the inherent nature of the fundamental elements, collectively forms the shared seeds of the four great elements—earth, water, fire, and wind. They then jointly utilize these seeds to manifest all external phenomena, including the material universe.

When each sentient being cognizes these phenomena, their own Tathāgatagarbha individually projects the outer appearances (outer manifestations) of the external objects onto the subtle sense faculties (indriya) within the brain, transforming them into inner manifestations (inner appearances), thereby forming mental images. When the inner six sense faculties contact the inner six sense objects (the inner manifestations), the Tathāgatagarbha then gives rise to the six consciousnesses. These six consciousnesses cognize the images of these phenomena. After this process, sentient beings mistakenly believe they are directly contacting real external objects. Hence, everything perceived by sentient beings is actually the inner manifestations solely projected by their own Tathāgatagarbha. All inner sense objects (inner manifestations) are illusory and unreal. The principle that "all phenomena with characteristics are illusory" (from the Diamond Sutra) refers precisely to this truth.

The items in one's own room are also co-manifested by the Tathāgatagarbha of the relevant sentient beings sharing collective karma. Sentient beings who are not connected to this karma do not participate in this manifestation through their Tathāgatagarbha. All the sensory realms (objects of the six senses) that a sentient being personally encounters are inner manifestations projected solely by their own Tathāgatagarbha and are unrelated to others. The seemingly real tables, chairs, benches, televisions, etc., appearing externally are co-manifested by the Tathāgatagarbha of the relevant sentient beings (including those who manufactured these items). These beings collectively cause the manifestation of the tables, chairs, benches, and television. When one sees them, one's own Tathāgatagarbha projects them again, forming an image within one's mind. What one sees is merely a mental projection.