Ultimate Truth and Conventional Truth

The mundane (世俗) refers to the world of the three realms, that is, the five aggregates (pañcaskandha), the eighteen realms (dhātus), and all the material worlds (器世间) of the universe. Mundane dharmas are the survival principles of the world of the five aggregates and the operating principles of the material worlds of the universe. All speech, reasoning, views, opinions, and disputes are entirely unfolded around this world of the five aggregates and eighteen realms. If there were no five aggregates, no principles whatsoever would appear; and the world of the three realms—the five aggregates and eighteen realms—together with all principles, is entirely in constant arising, ceasing, and changing.

Satya (谛) means truth. The mundane truth (世俗谛) is the truth concerning suffering, origination, cessation, and the path of the world of the five aggregates—the truth that the world of the five aggregates is suffering, empty, impermanent, and without self. Because no matter what era or historical background, the Four Noble Truths of suffering, origination, cessation, and the path never change, they are called satya (truth).

The ultimate truth (真谛) is the most real principle, the truth of ultimate meaning (第一义谛), the supramundane truth (胜义谛), the most supreme and incomparable true principle in and beyond the world. This refers to the true mind of suchness, the tathāgatagarbha, which is the reality and the principle of the operation of the true mind, the tathāgatagarbha. The ultimate truth and the mundane truth are often fused together and function jointly; only when the two are fused together do all the principles and operating laws of the world of the five aggregates exist, does the world of the three realms exist, and does the mundane truth exist.

Since satya is truth, the true principle of all dharmas, representing great wisdom, the mundane speech of ordinary worldly people cannot possibly be satya, cannot possibly possess truthfulness; it is usually replete with wrong view (mithyā-dṛṣṭi) and folly, is not satya, and cannot be called the mundane truth. Only the Four Noble Truths taught by the Buddha are the mundane truth, because the Four Noble Truths speak of the truth of suffering, origination, cessation, and the path of the world of the five aggregates, possessing truthfulness; by cultivating in accordance with them, one can attain liberation and escape the cycle of birth and death. What ordinary worldly people say cannot be the mundane truth. If what worldly people said were the mundane truth, then all worldly people would be great saints who are liberated, and there would be no need for the Buddha to laboriously come to this evil world of the five turbidities to proclaim the truth of the mundane truth.

Since the ultimate truth is the truth concerning the true suchness of the real aspect (实相), then no matter how sentient beings view problems from the standpoint of the Buddha's Dharma, it is never the ultimate truth; it remains the views and opinions of the individual's deluded perceiving mind, usually full of wrong views and errors. Even if there were no wrong views and everything were correct principle, it still would not be the ultimate truth, the tathāgatagarbha. The ultimate truth refers to the true principle-substance of the real aspect, the tathāgatagarbha suchness that is neither arising nor ceasing, neither defiled nor pure (na saṃkleśo na vyavadānam), neither increasing nor decreasing, neither interrupted nor permanent. No speech, words, views, or opinions can represent the substance of suchness; therefore none of them is the ultimate truth—they are merely deluded knowing and deluded awareness.