The doctrine of buddha-nature—the innate enlightened nature of mind—is found in all Mahāyāna Buddhist traditions, but it was not present in early Buddhism and is not accepted by most contemporary Asian Theravada Buddhist traditions. In mainstream Theravada, consciousness is one of the five aggregates, the conditioned aspects of existence which are left behind upon the attainment of nirvāṇa. The notion of a mind that exists apart from the aggregates, which is primordially pure and somehow innately enlightened, would be heretical to most Theravada Buddhists. As the contemporary Western Theravadin teacher Ṭhānissaro Bhikkhu has written, "The Buddha never advocated attributing an innate nature of any kind to the mind—good, bad, or Buddha." Not only are the buddha-nature teachings not true, he continues, but they hinder one's progress on the path: "If you assume that the mind is basically good, you'll feel capable but will easily get complacent."[1] This is not a universal view; the Thai Forest tradition that began at the turn of the twentieth century espouses the view that the mind is "luminous" in the sense of being innately pure, nondual awareness, and that it continues to exist in nirvāṇa.
All Mahāyāna traditions teach that because all phenomena arise in dependence on other phenomena they are empty of any self-nature. How to describe that emptiness, however, is a matter of considerable disagreement. Whereas Yogācāra masters use positive language to describe the mind and the true nature of reality, in the Madhyamaka philosophy of Nāgārjuna and his disciples, only negative language can be used. "Because there are no phenomena that are not dependently arisen," Nāgārjuna wrote, "there are no phenomena that are not empty."[2] Thus while buddha-nature is generally accepted in Yogācāra, in Madhyamaka it is considered either provisionally (that is, not literally) true or a synonym for emptiness.
Buddha-nature is a central doctrine in all East Asian Buddhism save for the Pure Land traditions. Almost all base their teachings on the Awakening of Faith in the Mahāyāna, a Chinese composition that introduced the concepts of original enlightenment and actualized enlightenment. The first is the fundamental nature of mind obscured by stains, and the second is that same innately enlightened mind freed of those obscurations. The Tiantai (Tendai in Japan), Huayan (Kegon in Japan), and Chan (Zen in Japan) and their offshoots all embraced buddha-nature, as did the tantric Shingon school in Japan, although there are differences in their approaches. Dōgen, one of the founders of Japanese Zen, taught that meditation is practiced not to attain enlightenment but to express one's innate enlightenment. This is expressed in the famous Zen proverb "If you meet the Buddha on the road, kill him." That is, if you think that the Buddha is someone or somewhere else, you're wasting your time; destroy that idea and realize your own innate enlightenment. In Pure Land there remains some disagreement, with some sects arguing that ordinary beings do not have buddha-nature but only acquire it upon being saved by the Buddha Amitābha and being born in the Pure Land.
The dominant Tibetan and Himalayan tantric traditions of Nyingma, Sakya, Kagyu, and Geluk are better understood as loose categories of affiliation than as closed systems, and leaders often move between monasteries to pursue their education. There is therefore no buddha-nature position that can be said to belong to any one particular tradition. Rather, buddha-nature teachings in Tibet are debated in terms of provisional versus definitive and whether buddha-nature is simply another word for emptiness or has qualities of its own. That is, the issue is whether buddha-nature is empty of all qualities (a position known as "self-emptiness") or is empty of all but its own qualities ("other-emptiness"). These conversations began in India but took on new life in Tibet, where buddha-nature theory is largely built around the fifth-century treatise the Ratnagotravibhāga, popularly known in Tibet as the Uttaratantra or Gyü Lama. These two poles of self-empty and other-empty are traditionally defined in Tibet as the analytic and meditative traditions of Ratnagotravibhāga exegesis. The analytic tradition largely relies on strict Madhyamaka presentations of emptiness and rejects any attempt to describe ultimate reality with positive characteristics. The meditative tradition encompasses a wide body of buddha-nature theory found primarily in the Jonang, Kagyu, and Nyingma traditions, usually, although not always, in some form of a unity of emptiness and luminosity.
In Western Buddhism few teachers seem overly concerned with maintaining a separation between their received tradition and the Buddhisms of other regions; collectively they have contributed to a new form of Buddhism marked by eclectic assortments of teachings and practices, all of which embrace buddha-nature as a core tenet, explicitly or otherwise. This is true even in the Vipassanā community, despite the objection of traditionalists such as the American monk Ṭhānissaro Bhikkhu mentioned at the beginning of this essay. For example, Sharon Salzberg wrote of a meeting in 1990 with the Dalai Lama during which she asked about self-hatred. The Dalai Lama responded with incredulity that any person would hate themselves: "But you have Buddha nature," he said. "How could you think of yourself that way?"[3] Jack Kornfield has a teaching series called "Your Buddha Nature" and leads retreats on the topic. Perhaps more than any other contemporary Western Buddhist, Joseph Goldstein models the modern Western synthesis of disparate Asian Buddhist traditions. His book One Dharma unites Tibetan Dzogchen and Zen with the Theravada Vipassanā tradition of the Burmese, Thai, and Bengali teachers that formed the major part of his training. Goldstein puts forward buddha-nature (or its synonyms) as the definition of wisdom in his One Dharma synthesis. He writes,
"In Buddhism there are many names for ultimate freedom: Buddha-Nature, the Unconditioned, Dharmakaya, the Unborn, the Pure Heart, Mind Essence, Nature of Mind, Ultimate Bodhicitta, Nirvana."[4]