Within the Sanlun understanding, emptiness and dependent origination are not two separate doctrines placed side by side, but two names for a single dynamic reality. All dharmas arise only through causes and conditions, and precisely because they are dependently originated, they lack any fixed, independent self-nature. This absence of inherent existence is what “emptiness” signifies. To see dependent origination clearly, then, is already to see emptiness; there is no hidden substance behind phenomena, only their relational, conditioned mode of being.

At the same time, Sanlun thought stresses that emptiness is not a negation of the functioning world. Because things are empty of any rigid, unchanging essence, they can appear, interact, transform, and cease through causal relations. If phenomena possessed true, independent existence, they would be static and could not genuinely arise or perish; real causality would be impossible. Emptiness, in this sense, is the very condition that allows dependent origination to operate, the enabling ground of the flux of experience.

This relationship is articulated through the framework of the two truths. On the conventional level, one speaks meaningfully of causes and effects, moral responsibility, and the entire web of dependent origination. On the ultimate level, those very dependently arisen phenomena are recognized as empty of self-nature. These are not two different worlds, but two perspectives on the same field of dependently arisen emptiness, a single reality seen under different lights.

Sanlun masters present this unity of emptiness and dependent origination as the Middle Way between asserting that things truly and independently exist and claiming that nothing exists at all. Phenomena are not sheer nothingness; they function and have conventional efficacy precisely as dependently originated. Yet they are not ultimately established in themselves, since their existence is only relational and conditioned. To realize that “emptiness is dependent origination, and dependent origination is emptiness” is to see how the ultimate truth does not cancel the conventional, but rather discloses how it is able to function at every moment.