The Anūnatvāpūrṇatvanirdeśaparivarta (AAN, Sanskrit, The Chapter on the Teaching of Neither Deficiency Nor Fullness), also known as the Sutra of Non-increase and Non-decrease (Chinese: 不增不減經) is a short Mahayana text belonging to the tathāgatagarbha class of Mahayana sutras. The main topic of the sutra is the nature of the Buddhist cosmos (the "realm of sentient beings", Skt. sattvadhātu) and its relationship with ultimate reality (dharmakāya, tathāgatagarbha, etc).

History

The AAN is only extant in the Chinese translation (Ch. Fóshūo bù zēng bù jiǎn jīng, 佛説不増不減經, Taisho no. 16) produced by Bodhiruci (6th century) at Luoyang circa 520 CE. The Tibetan tradition is unaware of this sutra.

According to Silk, the AAN, while difficult to date, "must be older than the early fifth century" since it "clearly predates the Ratnagotravibhāga". He also argues that "given its doctrinal standpoint and style of presentation, I believe that it post-dates the Tathāgatagarbha-sūtra and Śrīmālādevī."

According to Karl Brunnhölzl, this sutra is notable for its doctrinal similarity to the Śrīmālādevī Sutra. Other scholars also note a close relationship between the teachings of the Anūnatvāpurnatvanirdeśa and other buddha-nature sutras like the Mahāparinirvāṇasūtra and the Tathāgatagarbhasūtra.

Three Chinese commentaries were written on the AAN (by Saichō, Wŏnhyo, and 榮業 (unknown author)), but none of them survive.

An English translation and analysis of the AAN was published by Jonathan Silk in 2015.

Main teachings

The One Realm (ekadhātu)

thumb|Bhutanese [[thangka (cloth painting) depicting the Buddhist cosmos pervaded by Buddhas and bodhisattvas, c. 19th century.]]

The first part of the AAN outlines various wrong views (mithyā-dr̥ṣṭi) which prevent sentient beings from obtaining knowledge of the ultimate truth. The second part of the text discusses the ultimate truth, the most important doctrinal element here being the absence of "decrease or increase" in the "realm of sentient beings" (Sanskrit: sattvadhātu, which is defined in the sutra as "the mass of beings, the ocean of beings"). This means that the overall number of living beings never increases nor decreases, despite all the things which happen and despite the fact that some sentient beings attain Buddhahood. This one domain is identical to both Buddhahood (i.e. the nirvāṇa-dhātu) and saṃsāra (the realm of cyclical suffering, i.e. sattvadhātu), both of which are non-dual and indivisible.

According to the AAN, neither sentient beings, disciples or solitary Buddhas can know this ultimate reality directly, they can only access it through faith. As the sutra states:<blockquote>This extremely profound purport is exactly the Tathāgatha’s sphere of insight and it is the range of the Tathāgata’s mind. Śāriputra, such a profound purport as this cannot be known by the insight of all the auditors and lone buddhas, cannot be seen, cannot be examined. Still how much less could all foolish common people fathom it. It is indeed only the insight of the buddhas and tathāgatas which can examine, know and see this purport. [Despite] the insight possessed by all auditors and lone buddhas, Śāriputra, with respect to this purport, they can only have faith; they are not able to know, see or examine it in accord with reality. (Silk, 2015, pp. 89-92) </blockquote>

The sutra goes on to equate this single reality with the ultimate truth (paramārtha-satya), with buddha-nature (tathāgatagarbha), with the Dharmakaya (Dharma body of the Buddha) and with the “originally pure mind” (prakṛtipariśuddhacitta).

The wrong views of increase and decrease

Furthermore, according to the sutra, thinking that there is increase or decrease in the dhātu (domain, element, realm) of sentient beings (as well as thinking that nirvana is annihilation) is a serious misconception that leads sentient beings to continue to wander in samsara. The Sutra of Non-increase and Non-decrease states:<blockquote>

As I have expounded, Śāriputra, the meaning of the dharma-body is inseparable from, indivisible from, not cut-off from, not different from the inconceivable qualities definitive of a buddha, greater in number than the sands of the Ganges, [namely,] the merits and insight of a tathāgata. It is like a lamp, Śāriputra, whose brightness, color and tactile sensation are inseparable and indivisible [from the lamp itself]. Again, it is like a maṇi gem whose characteristics of brightness, color and form are inseparable and indivisible [from the gem itself]. (Silk, 2015, pp. 96-98 §11, 12)</blockquote>

This idea is an important source for the Ratnagotravibhāga<nowiki/>'s fifth vajra point, and this text quotes the Sutra of Non-increase and Non-decrease on this topic. In Chinese Buddhism, this doctrine was interpreted in terms of essence-function (ti 體 and yong 用).

According to the Sutra of Non-increase and Non-decrease, the buddha-nature - dharmakaya is also the eternal ground or basis of all things or dharmas (phenomena).

  • Ordinary sentient beings: when the dharmakaya is "ensnared by limitless defilements greater in number than the sands of the Ganges, drifting on the waves of the world from beginningless ages, comes and goes through birth and death”.
  • Bodhisattvas, which refers to when the dharmakaya "repels the anguish and suffering of birth and death in the world, banishes all desires, practices the ten perfections, collects the eighty-four thousand teachings, and cultivates the practices leading to bodhi".
  • Buddhas, described in the AAN as follows: “This very dharma-body, thoroughly freed of all sheaths of defilements, having transcended all sufferings, the stains of all defilements vanished, well and truly pure, fixed in the Absolute Reality that is ultimately pure, risen to the stage looked forward to by all beings, having attained peerless heroic strength with respect to all spheres of knowledge, perfected in sovereign power over all things free of all hindrances and unobstructed."

As such, buddhas, bodhisattvas and sentient beings are not different in terms of their essential nature (their only difference is in the relative state of the covering defilements) and are all therefore not ultimately subject to increase or decrease.

According to Silk, the view that "all of reality is unitary" is the key to the vision of the AAN. While there are three different aspects or modalities of this unitary reality, they are all one realm, a single essence, which is the common ground for all things. It is only due to the adventitious defilements that this inherent unity is not seen by some. This "cosmic unity" which holds that there is one single reality has been termed a type of monism by Jonathan Silk. Christopher Jones similarly writes that this sutra is defending an "absolute principle," which is the dharmakāya filled with buddha qualities. All living beings, and all of reality, are merely modes of this absolute reality which also represents "the common nature possessed by all beings".