Within the Sanlun tradition, emptiness is understood as the absence of any fixed, independent self-nature in all phenomena. Things do not possess an inherent essence that makes them what they are from their own side; rather, they arise only through causes, conditions, and mutual dependence. To see that all things are empty in this sense is not to deny their appearance or their functioning, but to recognize that what appears is contingent, relational, and without a permanent core. This insight is grounded in the teaching of dependent origination and serves to loosen the grip of reified concepts about self and world.

Sanlun articulates this vision of emptiness through the framework of the two truths. On the level of conventional truth, the world of distinctions, names, moral causality, and practice operates meaningfully and effectively. On the level of ultimate truth, those very distinctions are seen as empty of intrinsic reality, lacking any unchanging substance. Yet these two truths are not separate realms; rather, they are two ways of regarding the same phenomena, one from the standpoint of everyday functioning and the other from the standpoint of their lack of inherent nature.

Emptiness in this school functions as the middle way between the extremes of eternalism and nihilism. Eternalism clings to the idea that things truly and permanently exist, while nihilism falls into the view that nothing exists at all or that conventional reality is simply negated. Sanlun insists that to understand emptiness properly is to avoid both extremes: phenomena neither possess absolute existence nor are they utterly non-existent. They exist conventionally, in dependence upon conditions, while being ultimately empty of any self-sustaining essence.

A distinctive feature of this understanding is the insistence that emptiness itself is empty. Emptiness is not a hidden substance, a metaphysical ground, or some ultimate “thing” standing behind appearances. Even the concept of emptiness is a dependent construction, useful as a teaching but not to be clung to as an absolute. In this way, the school guards against turning emptiness into yet another object of attachment, showing that the medicine of doctrine must itself be relinquished once its therapeutic work is done.

Methodologically, Sanlun employs a rigorous dialectical and refutational approach to express this insight. By systematically negating all fixed views—whether of existence, non-existence, both, or neither—it reveals the limits of conceptual thought in capturing ultimate reality. This deconstruction of views is not mere intellectual play; it is a practical means to dissolve attachment, conceptual proliferation, and the discriminative thinking that underlies suffering. When emptiness is realized in this way, wisdom arises, and the mind becomes free from the compulsion to solidify either self or world.