What is Nibbaana? Does it exist? Is it merely the cessation of avijjaa? There seems to be so many different questions concerning the summum bonum
of Buddhism, and so many conflicting answers depending on what tradition, teacher, and text one chooses to reference. It is simply enough to make one's head spin.
I find the overall debate pretty pointless since everyone seems to be arguing over something which they have yet to attain, however, the Abhidhammattha Sangaha
does has some interesting things to say about Nibbaana. On page 315 of the 1968 edition translated by the Venerable Narada Maha Thera it states:
Nibbaana however is termed supramundane and is to be realized by the wisdom of the Four Paths. It becomes an object to the Paths and Fruits, and is called Nibbaana because it is a departure (ni) from cord-like (vaana) craving.
Nibbaana is onefold according to its intrinsic nature.
According to the way (it is experienced) it is twofold-namely, the element of Nibbaana with the substrata remaining and the element of Nibbaana without substrata remaining.
It is threefold according to its different aspects-namely, Void (60), Signless (61), and Longing-free (62).
Great seers who are free from craving declarfe that Nibbaana is an objective state (63) which is deathless, absolutely endless, non-conditioned (64), and incomparable.
This, as fourfold, the Tathaagatas reveal the Ultimate entities:-consciousness, mental states, matter, and Nibbaana.
In the Abhidhamma Compendium this is the sixth chapter which deals with th analysis of matter.
It's gets even juicier in the notes on page 318:
Nibbana is also derived from ni + (symbol I can't make that looks like a check mark) vaa, to blow. In that case Nibbaana means the blowing out, the extinction, or annihilation of the flames of lust, hatred, and ignorance. It should be understood that the mere destruction of passion is not Nibbaana (khayamattam' eva na nibbaananti vattabbam). It is only the means to gain Nibbaana, and is not an end in itself.
Nibbaana is an ultimate reality (vatthudhamma) which is supramundane (lokuttara), that is, beyond the world of mind and body or the five 'aggregates'.
Nibbaana is to be understood by intuitive knowledge (paccakkha or pativedha ~aana and anumaana or anubodha ~aana). To express both ideas it is stated that Nibbaana is to be realized by means of the wisdom pertaining to the four Paths of Sainthood and that it becomes an object to the Paths and Fruits.
Intrinsically (sabhaavato) Nibbaana is peaceful (santi). As such it is unique (kevala). This single Nibbaana is viewed as twofold according to the way it is experienced before and after death. The text uses a simple but recondite Paali phrase-kaarana-pariyaayena. The Ceylon Commentary explains-the cause for naming it as such with respect to its having or not having the aggregates as the remainder (sa-upaadisesaadivasena pa~~aapane kaaranabhuutassa upaadisesabhaavassa lesena). Adding a note on this term S.Z. Aung writes: "The Ceylon commentaries explain it by pa~~aapane kaaranassa lesena - by way of device of the means (of knowing) in the matter of language" Compendium, p. 168, n. 6.
And, further concerning Nibbaana it states on page 319-20:
60. Su~~ata - Devoid of lust, hatred, and ignorance, or of all conditioned things. Void here does not mean that Nibbaana is 'nothingness'.
61. Animitta - Free from the signs of lust etc., or from the signs of all conditioned things.
62. Appanihita - Free from the hankerings of lust etc., or because it is not longed for with any feelings of craving.
63. Padam - Here the term is used in the sense of an obkective reality (vatthudhamma). State does not exactly convey the meaning of the Paali term. It may be argued whether Nibbaana could strictly be called either a state or a process. In Paali it is designated as a 'Dhamma'.
64. Asankhata - Nibbaana is the only Dhamma which is not conditioned by any cause. Hence it is eternal and is neither a cause nor an effect.