Vijñaptimātratā refers solely to the three transforming consciousnesses, which manifest and reveal all phenomena. "Mind-only" means solely the Tathāgatagarbha true mind, from which all dharmas are transformed and produced.
Dharmas manifested solely by another individual's consciousness are only that individual's five aggregates of the material body. All other dharmas are either collectively manifested by the consciousnesses of sentient beings or individually manifested by a single consciousness. The five-aggregate body and mind individually manifested by others, which we come into contact with or perceive, are in fact dharmas individually manifested by our own consciousness. The "consciousness" in Vijñaptimātratā denotes the three transforming consciousnesses, meaning that without exception, all dharmas contacted and cognized by us sentient beings are solely manifested by our own three transforming consciousnesses.
For the sixth consciousness, seventh consciousness, and the five sense consciousnesses, external objects exist; what the sixth consciousness cognizes are internal objects. But for Tathāgatagarbha, what dharma could possibly exist outside it? Chan masters often say: "Outside the mind, not a single dharma exists; the green mountains fill one's sight." This means that beyond the Tathāgatagarbha mind, no dharma exists whatsoever—all dharmas, such as green mountains and the like, are but phenomena within the Tathāgatagarbha's own mind.
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