Grief (novel)
During the course of the novel, the ideas of the stages of grief are introduced. The stages are denial, anger, depression, and acceptance. The narrator, as well as other characters in the story, slowly passes through these stages in trying to deal with death.
Nirvana (Buddhism)
The Theravada tradition identifies four progressive stages. The first three lead to favorable rebirths in more pleasant realms of existence, while the last culminates in nirvana as an Arahat who is a fully awakened person. The first three are reborn because they still have some of the fetters, while arhat has abandoned all ten fetters and, upon death will never be reborn in any realm or world, having wholly escaped "saṃsāra".