What is Meant by Non-Natural and Non-Conditioned Nature?

The Buddha in the Śūraṅgama Sūtra states that all phenomena do not exist naturally, nor do they arise from the combination of causes and conditions; rather, they are manifestations of the Tathāgatagarbha nature. For example, consider the trees on a mountain. If they were said to exist naturally, they would naturally perish. After perishing, would they naturally regenerate? They would not. Moreover, many trees are artificially planted. Even those not planted by humans did not arise naturally; they gradually appeared along with the emergence of the Earth.

Are trees then produced by the combination of causes and conditions? They are not. Superficially, the appearance of trees seems to result from the combination of causes and conditions such as human planting, watering, irrigation, fertilization, sunlight exposure, and so forth. In reality, this is not the case. These dharmas of dependent arising are illusory, subject to birth, cessation, and change; they lack substantial function. The substantial function belongs to the Tathāgatagarbha. It is the Tathāgatagarbha that aggregates the five great elements to form them. Without the five great elements, there would be no trees; even the minute particles of the tree’s cells would not appear. Even these external dharmas of dependent arising are themselves aggregates formed by the seven great elements of the Tathāgatagarbha. There are no truly substantial dharmas of dependent arising. Therefore, trees possess the nature of the Tathāgatagarbha. When sentient beings perceive trees, it is the marvelous function of the Tathāgatagarbha’s seeing-nature and Buddha-nature; it is the wondrous true-suchness nature.