Producing means manufacturing, which requires funds and raw materials. The manas does not have these things; He has no storehouse and cannot store them. Only the tathāgatagarbha is endowed with these dharmas and possesses the seeds of all dharmas, and thus can create all dharmas—this is equivalent to the role of the producer. The tathāgatagarbha produces according to karmic seeds, and the karmic seeds are the tathāgatagarbha's selection; this is the conditioned (saṃskṛta).
The tathāgatagarbha also has a conditioned nature; all dharmas are brought forth through the conditioning activity of the tathāgatagarbha. If the tathāgatagarbha were completely unconditioned and paid no attention to anything at all, the world would not arise and exist, the five aggregates would not exist, and even the manas would not exist. What kind of film is made is indeed decided by the tathāgatagarbha, not by the manas—the manas cannot be the master of it. Once the film is decided, the karmic retribution is decided, and cause and effect are thereby requited.
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