According to comments, this question isn't getting the kind of answer that the OP wants.
How about I rewrite it as follows, e.g. is this still the question which the OP wanted to ask, and clearer?
How is nibbana complete, and unconditioned?
How can nibbana (i.e. an Arhat's attainment of nibbana) be complete or final?
I ask because e.g. the psychology of (therapy for) addictions warns that relapses are possible.
I think that psychology, and the experience of addicts and addiction counsellors, warns that relapses are possible and remain possible. So, once a person is ever addicted to something (e.g. obviously substance abuse, but I presume anything else too -- e.g. anger, sensuality, or so on), then common experience shows that if one abstains from something and then re-engages in it, it is as fast back to the former level as it once was.
This is why relapse prevention in therapy is so important -- i.e. because old styles of thinking and behaving are never completely erased, but are just lying dormant: they are inactive at the moment BUT NOT ERASED, i.e. the "roots" remain.
How can nibbana even be described as "unconditioned"? Given that the brain, people's behaviour, and experience and habits and so on, is all conditioned, how can nibbana not be?
Is there a sutta which (explicitly) explains why nibbana is considered unconditioned? Is it existent as well as unconditioned?
I especially want a reference to a sutta, if you can, not only an unreferenced answer.
Also is there anything in the sutta pitaka that would help me understand whether nibbana is conditioned by the brain of the practitioner -- or if not, then why not? Or, even if not the "brain", then by the practitioner's "condition" in general (e.g. their surroundings, environment)?
Tags: [pali-canon] [reference-request] [ nirvana]