Nibbāna

Aspects
There is first of all the ethical aspect, for Nibbāna implies the destruction
of evil propensities (āsavā), the removal of moral hindrances
(nīvaraṇa), the freeing from all fetters (saṁyojana). In view
of these removals, Nibbāna is called deliverance (vimutti). Where
Nibbāna cannot be aimed at as a positive goal—for, “not by striving
can world’s end be reached” 2 —striving becomes possible in the
overcoming of the hindrances and obstacles.
Then there is the aspect which is more mental than moral, because
it is the culmination of an evolution in the process of comprehension.
It is the gradual development through the four stages
of sainthood, from learner to adept (asekha), from stream-enterer
(sotāpanna) to arahant. And as this process is not one of acquisition
of learning or virtue, but is leading rather to no more becoming, it
may be labelled a process of cessation (nirodha), with Nibbāna as
the ending of becoming (bhava nirodha).
And finally, there is the philosophical and metaphysical aspect,
which lends the concept a kind of positive character, even though
most of its synonyms are negative. As such, Nibbāna is viewed as
the deathless (amata), the unconditioned (asaṅkhata), the summum
bonum (parama sukha). It is the one absolute in which there is no
relativity and hence no distinction or division of ‘self’ and ‘non-self’,
2 Gamanena na pattabbo lokasanto kudācanaṁ: Ang. N. IV.
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