Hua Yan thought turns again and again to the vision of a cosmos in which nothing stands alone and nothing obstructs anything else. At its heart lies the teaching of mutual interpenetration between principle (li) and phenomena (shi): the underlying reality and the myriad appearances are not two separate realms, but fully present in one another. Every particular thing contains the whole, and the whole is expressed in every particular, so that individuality and totality coincide without conflict. This is often articulated through the image of Indra’s Net, an infinite web of jewels where each jewel reflects all the others, suggesting a universe of complete mutual reflection and interdependence. The same insight is captured in the claim that “one is all, and all is one,” where each event or being both depends on and reveals the total network of conditions.

This vision is given systematic form in the teaching of the Dharmadhātu, the “realm of reality,” understood as a perfectly harmonized network of principle and phenomena. Hua Yan masters describe a fourfold Dharmadhātu: the realm of principle, the realm of phenomena, the non-obstruction between principle and phenomena, and the non-obstruction among all phenomena. In this fourfold structure, the absolute and the relative, emptiness and form, are seen as perfectly interfused rather than opposed. The doctrine of dependent origination is thereby radicalized: every event arises not just from a few causes and conditions, but from an immeasurable web of interrelations extending throughout space and time. Time and space themselves are viewed as non-obstructing, such that past, present, and future, here and there, mutually condition and illuminate one another.

From this standpoint, reality is characterized by perfect harmony and mutual identity, often described as “roundly interpenetrating and harmonious.” Apparent dualities—samsara and nirvāṇa, purity and impurity, self and others—are reconciled within a non-dual vision in which conflict gives way to dynamic complementarity. Emptiness here does not imply a void, but the absence of isolated, self-sufficient existence, which allows for the fullest possible interconnection. Because all beings and realms are intertwined in this way, the Hua Yan tradition emphasizes a bodhisattva ideal in which deep insight into interdependence naturally flowers as universal compassion. The bodhisattva embodies the integration of wisdom and compassionate activity, responding to the needs of all beings within this jeweled, mutually containing universe portrayed so vividly in the Avataṃsaka Sūtra.