What Is the Meaning of the Beginningless Ignorance and the Ignorance of a Single Thought?

Fundamental ignorance, as the name implies, means that one's views and concepts are ignorant and defiled. Why are they ignorant and defiled? Because there is a self in the mind, taking the five aggregates (pañcaskandha) and eighteen realms (dhātus) as self and what belongs to self, not knowing that this so-called self is suffering, empty, impermanent, and not-self. All of one's views and concepts revolve around self and what belongs to self, firmly grasping this so-called self, and thus birth and death also become firm. When one's bodily, verbal, and mental actions are guided by the notion of a self, of course body, speech, and mind are all defiled karma, and from this defiled karma, the turning of birth and death inevitably continues without cease. Therefore fundamental ignorance can perpetuate all birth and death, and liberation cannot be attained.

However, fundamental ignorance is also a kind of beginningless ignorance (avidyā); it has existed throughout beginningless kalpas, with no point of beginning. If there were a point of beginning, then before that time there would have been no fundamental ignorance, and sentient beings would be arhats, abiding in nirvāṇa without remainder (anupadhiśeṣa-nirvāṇa). In nirvāṇa there are no sentient beings, nor any arhats. All ignorance has existed innately since before beginningless kalpas; it is all beginningless ignorance, and it is only through the conditioning of later circumstances that beginningless ignorance is increased or decreased.

After fundamental ignorance has been completely eliminated, there is still beginningless ignorance that must be completely eliminated before one can become a Buddha. Beginningless ignorance means that sentient beings, throughout beginningless kalpas, have always taken the world of the five aggregates to be real, not knowing that it is an illusory appearance conjured forth by the tathāgatagarbha, not knowing that it is empty. It is from this that there is grasping at self and grasping at dharmas, and thus segmented birth-and-death and transformational birth-and-death, and liberation is impossible. To eliminate beginningless ignorance, one must investigate Chan (dhyāna), personally realize the tathāgatagarbha, and personally realize the tathatā nature of all dharmas, step by step realizing the nature of the one true dharma realm. When the tathatā dharma-nature of all dharmas has been realized, consciousness will be completely transformed into wisdom, and the Buddha's path will be accomplished.