All dharmas of body and mind return to the Tathagatagarbha.

As the name suggests, mental factors are dharmas that belong to the mind. Emotions, attitudes, opinions, suggestions, anxiety, anger, jealousy, sadness, and so forth are all dharmas that arise in the mind, belonging to the dharmas possessed by the mind, and are therefore called mental factors. Dharmas that arise in the body, belonging to the dharmas possessed by the body, are, as the name implies, called bodily factors. Dharmas possessed by the physical body, such as falling ill, changes in weight, various occurrences of incidents, the arising of something, or the diminishing of something, etc.—all the arising, ceasing, and transformations within the body are bodily factors. The physical body is divided into the inner body and the outer body. The inner body is the physical body itself, while the outer body consists of the six sense objects: form, sound, smell, taste, touch, and mental objects. Together, they constitute the five aggregates body. The body is a material dharma, and the dharmas that arise in the body are also material dharmas. Therefore, what belongs to material dharmas is also material dharmas. All dharmas belonging to the body are also dharmas belonging to the mind. To which mind does this refer?

All worldly dharmas are divided into material dharmas, mental dharmas, and dharmas that are neither material nor mental. Their attributes are divided into dharmas possessed by the mind, dharmas possessed by the body, and dharmas possessed by neither body nor mind. All these dharmas are subsumed and attributed to the Tathagatagarbha. Once all dharmas are subsumed into the Tathagatagarbha, there is nothing at all. What is there for us to cling to now? They are all empty, all illusory appearances. Yet, alas, the habitual tendencies of clinging are too deeply rooted and too difficult to transform. The root cause is that the ultimate reality of the dharma realm has not been understood clearly, not seen distinctly. This matter requires three asamkhyeya kalpas to be thoroughly clarified. After that, everything will change, and spiritual practice will come to an end.

The Mental Factors of Sentient Beings

What mental factors are operating within recollection? What mental factors are operating within thought? What mental factors are operating within investigation? What mental factors are operating within deliberation? What mental factors are operating within contemplation? What mental factor is understanding? What mental factor is willingness? What mental factors are operating within hope? What mental factor is comprehension? What mental factors are operating within planning? What mental factor is anticipation? What mental factor is blessing? What mental factors are operating within the power of vows?

What mental factor is realization, verification, and knowing? What mental factor is agreement, approval, and concurrence? What mental factor is being mindful without interruption? What mental factor is the lingering image in the mind that cannot be dispelled? What mental factor is remembering without forgetting? What mental factor is keeping firmly in mind? What mental factor is unwavering steadfastness? What mental factor is focusing the mind on one point? What mental factor is gazing without blinking? What mental factor is innate conscience? What are the functions of the mental factor of volition? What are the functions and effects of the mental factor of perception?

The states of mind, characteristics of mind, temperament, disposition, and nature all belong to mental factors. They may be wholesome, unwholesome, or neutral. Strictly speaking, mental factors are not limited to fifty-one. If one were to classify them in detail, there would be at least several hundred or even a thousand. Bodhisattva Vasubandhu merely made a broad and rough summary, categorizing them into fifty-one, which is not comprehensive. If the Buddha were to summarize these mental factors, it would be extremely subtle. Therefore, in our study of Buddhism, while we can rely entirely on what the Buddha said, we may rely on others as well, but we must exercise discretion and possess the ability to adapt flexibly.

Even when relying on what the Buddha said, one should have a certain capacity for adaptation. Fully understanding what the Buddha said is also extremely difficult. Sometimes there are certain differences and gaps between the Buddha's words and the Buddha's intent; they are not entirely consistent. Because the wisdom of sentient beings is limited, the Buddha cannot fully express his meaning directly. He often speaks implicitly, skillfully. When wisdom is insufficient, it is easy to misinterpret. Many people explain the Buddhist sutras, but in fact, they are not explaining the Buddha's original intent. The phenomenon of distorting the Buddha's meaning is too common and ordinary. The Buddha also endures this, although there is no mind that endures.