The Buddha-dharma has two meanings: one refers to the dharma taught by the Buddha, all the methods by which one can attain buddhahood and liberation; the other refers specifically to the tathāgatagarbha dharma. Of these two meanings, one is narrow and one is broad; most of what the Buddhist sūtras speak of as the Buddha-dharma refers to the tathāgatagarbha dharma.
All dharmas are manifested by the tathāgatagarbha. So are the non-Buddhist teachings also manifested by the tathāgatagarbha? Of course they are. Without the tathāgatagarbha, there would be no non-Buddhists and no non-Buddhist teachings; apart from the tathāgatagarbha, there would be no good people or evil people, no wholesome dharmas and no false dharmas.
Apart from the tathāgatagarbha, everything is false and illusory, but false dharmas have the functions of false dharmas; in particular, the function of wholesome dharmas can counteract unwholesome dharmas. One need only not crave and cling to wholesome dharmas, and subsequently even better wholesome dharmas will appear.
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