Can Buddhist Practitioners Use Non-Buddhist Methods?

What is called non-Buddhist dharma refers to dharmas that do not belong to the tathāgatagarbha—dharmas taught apart from the mind of tathāgatagarbha. Many non-Buddhist dharmas are of great use to Buddhist practitioners, so do not reject useful non-Buddhist dharmas. When a doctor treats a patient, that too is a non-Buddhist method. Can we do away with non-Buddhist methods and use only the tathāgatagarbha dharma to resolve everything? Clearly not. Non-Buddhists eat, and we must eat as well; non-Buddhists live on this earth, and we cannot leave the earth either; non-Buddhists breathe air, and we breathe the same air together with them. Since beginningless kalpas, we have never been apart from non-Buddhist dharmas, and after taking up Buddhism we must still cultivate dharmas that are the same as those of non-Buddhists—this is necessary. Apart from lacking the dharma of the tathāgatagarbha and the dharma of the non-self of the five aggregates, non-Buddhists possess all other dharmas, and we must be endowed with them as well. For example, their sense of renunciation, their aspiration for liberation, their meditative concentration (samādhi), and their various methods for resolving problems of the physical body are all well worth our learning; as long as they are useful to us, we should use them. In fact, all non-Buddhist dharmas are tathāgatagarbha dharmas. Even when a doctor cures a patient's illness, it is the tathāgatagarbha that cures it; in essence, it is still the tathāgatagarbha dharma. No person or dharma can ever be separated from the tathāgatagarbha; all are produced by the tathāgatagarbha, and in their essence all are the tathāgatagarbha.