text:
(Why) did the Buddha teach rebirth?

Was rebirth introduced in the First or Second Turnings, and why did the Buddha teach it? E.g. was it necessary to understand emptiness, causality, etc.?
For example, I imagine that some "reasons why" might include:

Maybe it helps deemphasize a person's current lifetime, highlighting its impermanence, so that one does not cling to it or themselves.
On the other hand, for some, it seems to be a source of inspiration to persevere on the Path, for a "good rebirth".

Would any of the Buddhist doctrines, excluding karma and rebirth, fail to make sense without rebirth?

The Buddha taught only facts and fundamental concepts, i.e. Re-birth.  Could you give some examples where avoiding the teaching/concept of rebirth make more sense in certain doctrines?

There must be a bunch of questions on this already... Did you search?

It appears rebirth has been discussed at length on tricycle, however, many of the links are dead.

@AndreiVolkov searched before, but did not find any answers to the question on why rebirth was taught by the Buddha.

The Buddha taught karma and rebirth under mundane right view -

Right view, I say, is twofold: there is right view that is affected by influxes, partaking of merit, ripening in the acquisitions; and there is right view that is noble, free of influxes, supramundane, a factor of the path.
AN 6.63

and as Bhikku Bodhi goes on to write in The Buddha's Teachings on Social and Communal Harmony

“Right view affected by influxes” implies that even as we attempt to see and act in accord with the Dharma, we are still affected by the delusion of self. “Partaking of merit” is using Buddhist practice for what we perceive as our own benefit. “Ripening in the acquisitions” means becoming or acquiring a self. These are mundane or worldly ways.

Since this mundane right view is still "affected by influxes", with notions of self, not only is rebirth unnecessary to understand not-self, it may in fact be incompatible, as further explained in this answer.
This may be why the Buddha taught  superior right view. It is this right view which leads to liberation, as Bhikku Bodhi writes -

This superior right view leading to liberation is the understanding of the Four Noble Truths. It is this right view that figures as the first factor of the Noble Eightfold Path in the proper sense: as the noble right view. Thus the Buddha defines the path factor of right view expressly in terms of the four truths: “What now is right view? It is understanding of suffering (dukkha), understanding of the origin of suffering, understanding of the cessation of suffering, understanding of the way leading to the cessation of suffering

Belief in rebirth (as reincarnation) is also unnecessary in regards to ethics and morality, as Bhikku Bodhi further writes -

Several texts testify that the Buddha himself seems to have recognized that morality can be established on the basis of self- reflection and ethical reasoning without requiring a belief in personal survival of death.

The Truth of Rebirth seems to be one of the larger points of dispute between participants on this site. See here and here for similar questions and answers. I guess this is not all that surprising to me since the site seems heavily represented by Western practitioners. In my experience it seems that westerners have (and I definitely include myself here) a particularly difficult time with the Truth of Rebirth as taught by the Buddha. Here is what Venerable Thanissaro Bhikkhu has to say about this:

Yet as these Buddhist religions have come to the West, they have run
into a barrier from modern Western culture: Of all the Buddha's
teachings, rebirth has been one of the hardest for modern Westerners
to accept. Part of this resistance comes from the fact that none of
the dominant world-views of Western culture, religious or
materialistic, contain anything corresponding to the idea of repeated
rebirth. Plato taught it, but — aside from an esoteric fringe — few in
the modern West have treated this side of his teaching as anything
more than a myth.
For people who have felt burned or repelled by the faith demands of
Western religion, there is the added barrier that the teaching on
rebirth is something that — for the unawakened — has to be taken on
faith. They would prefer a Buddhism that makes no faith demands,
focusing its attention solely on the benefits it can bring in this
life.

There seem to be many approaches on this site:

Simply denying outright that the Buddha taught rebirth.
The Buddha taught the reality of rebirth as a (re)birth that takes place in this very life whenever self-views of "I" and "mine" occur. No "afterlife" concept of rebirth was taught or acknowledged by the Buddha.
Admitting he taught it, but insisting it was just skillful means.
Rebirth as a combination of metaphor and upaya.
Those who take rebirth at face value, but insist that mere experience can end.
Like above, but do not posit an end to this mere experience.
Those who think rebirth (generally) can be known incontrovertibly through reason alone.
Those who think rebirth requires a dose of faith to be known (generally).

And probably a number of other views that I've missed. Myself, I'm with 6 and 7.
Was rebirth introduced in the First or Second Turnings, and why did the Buddha teach it?
To my mind, unquestionably it was taught and introduced. I think the Buddha taught it because it was/is a conventional truth and the Buddha taught the truth.
Would any of the Buddhist doctrines, excluding karma and rebirth, fail to make sense without rebirth?
Yes, I think there are obvious logical problems and inconsistencies that present if you deny the truth of rebirth. For instance, as BodhiWalker mentions above one could seek the end of suffering by merely ending this current life. Even more problematic, one could "liberate" others from suffering by murdering sentient beings painlessly. That's monstrous and I want nothing to do with it. I want to make quite clear, I'm sure this is not what others have in mind when denying or glossing the truth of rebirth. I'm emphatically not concluding that those who deny or gloss the truth of rebirth are murderous monsters, just that denying or glossing the truth of rebirth presents logical problems that I don't see a way around.
Anyway, I think Venerable Thanissaro Bhikkhu's article above is excellent and highly recommend reading it many times and contemplating these questions.

I scored this answer down because it did not once mention the reality of rebirth.

@Dhammadhatu can you explain what you mean by "the reality of rebirth?" I really would like to understand what you are saying

What kind of edit would you suggest to the answer to improve it?

The answer neglected the 're-birth' the Buddha taught, which is the production of self-views that give birth to the idea of self; as described in many suttas, such as SN 22.81, which says: "The uninstructed assumes form, feeling, perception, formations, consciousness to be self. That assumption is a fabrication. Now what is the cause, what is the origination, what is the birth, what is the coming-into-existence of that fabrication? To an uninstructed, run-of-the-mill person, touched by that which is felt born of contact with ignorance, craving arises. That fabrication is born of that. "

Ok, i will try to reflect this understanding in my list and edit it to be clear that the part about westerners is my only reflective of my own experience/opinion. Do you regard the Buddha teaching about the knowledge he gained of his past lives during his night of awakening as similar descriptions of self-views that took place in Siddhartha's regular mortal life? I only ask as a point of clarification and not to try and challenge your understanding...

Your patience is excellent. Well done! As for the Buddha, he did not experience any "past lives", as confirmed by this proper translation of SN 22.79: https://suttacentral.net/sn22.79/en/bodhi Regards

@Dhammadhatu I was referring to  https://www.accesstoinsight.org/tipitaka/mn/mn.036.than.html where it is quoted as, "I directed it to the knowledge of recollecting my past lives. I recollected my manifold past lives, i.e., one birth, two...five, ten...fifty, a hundred, a thousand, a hundred thousand, many eons of cosmic contraction, many eons of cosmic expansion, many eons of cosmic contraction & expansion" ... what is your understanding of this sutta?

@YesheTenley Indeed. Dhammadhatu points to "pubbenivāsa" which is used in that phrase, and says that should be translated as "past abodes" rather than like "past lives", and that it's about self-views. One of his habits on this site is to say so, whenever the topic of rebirth comes up, and to downvote every answer which doesn't say the same. See also these topics, and/or he recommended this essay.

Ok, I've edited #2 to reflect this understanding as best I'm capable.

@YesheTenley I think there are obvious logical problems and inconsistencies that present if you deny the truth of rebirth. ... Those hypothetical problems that follow, to my knowledge, weren't addressed by the word of the Buddha, nor do I know if they are even fundamental enough to ponder. My concern is more with how would the core teachings e.g. 4 Noble Truths, Emptiness, or Causality, fail to make sense without belief in rebirth.

@YesheTenley thank you for your generous answer and directing me to the article. It may answer my questions. What concerns me, is that something is repeated so many times that one believes it without question, and may argue from a place that already assumes it to be true.

He says You take these matters on faith until you can confirm them for yourself. which troubles me. Faith in Buddhism as I understand it, is confirming things for yourself before you believe them.

@avatarKorra You might ask a separate question. Currently you're asking, "how (if it all) does rebirth (or a lack of faith in rebirth) affect one's understanding of the three characteristics?" A slightly separate question (but which might be closer to the question you want to ask) is, "Is it possible to understand and benefit from the doctrine of the three characteristics, without holding a belief in rebirth?" I guess the answers are, "Yes, faith in rebirth has some effects on the doctrines, and, yes it's possible to (many people do) also make sense of the doctrine even without that belief."

@avatarKorra Perhaps you should rewind your edit of this question as ChrisW has said and ask a separate question so that people are not confused when visiting this OP and seeing the questions/answers not align...

@ChrisW what you said about asking a separate question makes sense.

Pertinent to this answer, though, apparently there are Buddhist traditions (e.g. Zen per the link) that do not require a belief in rebirth, so presumably these traditions do not see any logical inconsistencies. That Buddhism can still have its soteriological effects, both with and without a belief in rebirth IMHO makes it all the more powerful.

The concept of rebirth is an axiomatic corolary of 'Karma'.
Also if rebirth does not exist then nibbana i.e. 'blowing out' doesn't make sense.
For e.g. without rebirth and without afterlife in heaven or hell you will be  essentially 'blown out' nibbanafied without doing anything.
So nibbana makes sense only because rebirth exist, because in rebirth the flame continues.
Also, murdering sentient beings (in a painless way) would also be equivalent to liberating them from suffering if rebirth does not exist.
So it is a pretty central doctrine, even if you don't emphasize on Karma.

Not really. If you get born in another realm due to your bad deeds in this life, then it makes sense to "strive" for nibbana. The 4 noble truths do not mention rebirth at all (nor does the noble eightfold path), but just that suffering exists and that it can be ceased. Now the 4 Noble Truths are higher teachings and most people I would assume haven't realized them..

@Val sorry i dont see exactly wherr are you contradicting my point. Yes it makes sense to strive for nirvana only because u are reborn in another realm. Also 4 noble truth and 8 fold path dont mention rebirth but they lead us to understanding of Karma through 'right action' and Rebirth is just extension of Karma.

@Val I would dispute that the Buddha did not teach rebirth or karma when he taught the 4NT. Both are implicit in dependent origination. See here: The Noble Truth of Rebirth

@BodhiWalker you could even add that murdering sentient beings (in a painless way) would also be equivalent to liberating them from suffering if rebirth does not exist

@YesheTenley okies added.

@BodhiWalker For e.g. without rebirth and without afterlife in heaven or hell you will be essentially 'blown out' nibbanafied without doing anything. doesn't causality and impermanence teach us that all composite phenomena, e.g. a house or a person, will eventually cease to exist without "doing anything" because it is by nature, impermanent?

@avatarKorra  impermenance more of implies the inherent 'change' in nature of composite phenomena...a person will cease to exist in the form he is in, which is infact happening every moment he is there...so when his body ceases in death that is not 'nibbana'...his energy survives in material and non-material form...ofcourse he no longer identifies with pervious self.

There are Buddhist traditions that do not require belief in rebirth. So Nibbana apparently makes sense. See this article.

@avatarKorra Which Buddhist traditions are you talking about?

@BodhiWalker - Gil Fronsdal, the author of the article says, "I have practiced in particular Buddhist traditions that do not require a belief in rebirth", then says Zen.
A faith in the Buddha's teachings such that the rest of the teachings no longer stand as truth without the promise of rebirth just seems very weak.

@avatarKorra faith in rebirth is not imperative to either practise or attaining Nibbana. IMO selective acceptance of Buddhas words to fit your own world view shows weak faith. My argument in the answer is not that Nibbana can be attained only with belief in rebirth, it that the whole doctrine has meaning only in context of rebirth.

I do not think the Buddha taught that it was necessary to assume rebirth.
Take this from the Kalama Sutta:

"'Suppose there is a hereafter and there is a fruit, result, of deeds
  done well or ill. Then it is possible that at the dissolution of the
  body after death, I shall arise in the heavenly world, which is
  possessed of the state of bliss.' This is the first solace found by
  him.
"'Suppose there is no hereafter and there is no fruit, no result, of
  deeds done well or ill. Yet in this world, here and now, free from
  hatred, free from malice, safe and sound, and happy, I keep myself.'
  This is the second solace found by him.

Clearly, any of the meditative practices the Buddha taught focus attention on the rebirth that happens in this moment, here and now.

Was rebirth introduced in the First or Second Turnings, and why did the Buddha teach it?
I think the idea of rebirth preceded (predated, already existed earlier than) the Buddha's doctrine:

Early Hinduism, Jainism and Buddhism
The idea of reincarnation has early roots in the Vedic period (c. 1500 – c. 500 BCE), predating the Buddha and the Mahavira.

I think that, therefore, the question[s] which the Buddhist doctrine had to answer included, "Is the 'rebirth' doctrine true, to what extent is it true (how does it fit with other Buddhist doctrines), what does it mean exactly, how does it work, what is kamma?" and similar questions.
Would any of the Buddhist doctrines, excluding karma and rebirth, fail to make sense without rebirth?
I don't know, maybe some of these might be affected:

Stages of enlightenment -- that perhaps you won't be enlightened in this life, but even so that's not too late (and that effort is always even though immediate result may seem impossible)
An incentive (albeit "siding with merit and resulting in acquisition") for morality: including, both, generosity and harmlessness
The concept of merit may affect the relationship between lay society and the sangha
The three characteristics:

anatta e.g. as explained in this answer -- if rebirth doesn't exist, does that mean that we live and die, and if so isn't that identifying with the aggregates?
anicca -- so you're saying that death is permanent, not impermanent?
dukkha -- without the doctrine of rebirth, some people may develop strange or wrong ideas around killing or suicide as being an escape from dukkha ... also the doctrine that "craving to live (or, for becoming)" and "craving to die (or, for cessation)" are, both, forms of craving

The superiority (super-humanity) of the Buddha (not according to the suttas, necessarily, but e.g. the Jataka tales and the Mahāvaṃsa)
Combining cyclic cosmology with the dhamma's being timeless (previous and future Buddhas)
Atheism -- no sense in worshipping the Gods too much, they too are subject to rebirth
Hope or optimism -- no matter how bad things seem now, etc.
Some sense in which dhamma is called timeless (akalika)

What do you mean by “hope or optimism”? The doctrine of rebirth seems much more pessimistic than materialism – there needs to be a lot of effort over numerous lives to achieve something that a materialist takes for granted as happening at the end of every single life.

More opportunities for a precious human birth in which to be fortunate, to hear the dhamma, to make some progress towards enlightenment, to help ... and more scope for agency (as opposed to e.g. helplessness) e.g. no "we are all predestined to die, so nothing we can do matters".

Other people might hope that their deceased beloved might have a favourable rebirth. Not everyone sees rebirth, or life, as nothing but a disaster (to be pessimistic of), even if that is one of the messages in the suttas.

First Noble Truth: saṃkhittena pañc·upādāna·k·khandhā dukkhā - In short, the five aggregates of clinging is suffering.
If all mental activities cease at death, there will be no craving after death as it is clearly a mental activity. If that's the case, apart from craving, the second noble truth should include things like breathing, eating, drinking, checking for vehicles before crossing the road and pretty much anything else that keeps you alive.
The third noble truth(s) would be both Nibbana and death.
Apart from the noble eightfold path that one needs to practice with years of dedication, the fourth noble truth(s) would include hanging yourself, shooting yourself, drowning, starving to death, death by lethal injection, sleeping on a railway, jumping from a skyscraper or pretty much doing whatever you like until you end up dead.
Imagine a criminal with such a belief saying "I became a serial killer so the government would make me enlightened by capital punishment."
Such a religion would mainly provide laughter to people instead of being taken seriously. :)

Maybe the Buddha knew that death is too painful and fearsome to consider - even if it did lead to cessation - so Buddhism gives us the possibility of an alternative path to liberation from suffering. In this lifetime. Without needing to rely on belief in a next one.

What's the point of such a colllosal effort if natural death leads to cessation of suffering?

Because ending suffering in this lifetime is better than the alternative of death.

The notion that the Buddha preached the Dhamma for 45 years and created a system of Sangha who have to follow 227+ vinaya rules and meditate for years with difficulty just to have enlightenment few  years in advance is comical at best. Why not use a painless method of suicide? :)

Please note that my critical questioning serves only to strengthen my faith, but to answer your question with another: why is it that most atheists/materialists don't commit suicide, having no belief in rebirth or afterlife? And further, why do 92%-95% of suicide attempts fail?

@avatarKorra it may be because of the fear of uncertainty even though they like to believe that it ends at death. Not willing to end experiencing of sensual pleasures etc.

yes if they had any real faith that it ends at death then there would be no fear to commit suicide; they'd all be doing it. They make the intellectual argument for it and yet, deep inside, no one really sees truth in it.

@avatarKorra I find talk of suicide kind of offensive and wrong. Firstly, plenty of people don't suicide: and the fact that they don't does not prove that they believe in rebirth nor that they believe in annihilation (so suicide is irrelevant to the argument). Second, it's considered very wrong to encourage people to kill themselves, e.g. by describing the advantages of death (e.g. saying, "If you kill yourself then dukkha will end for you") -- it may be considered similar to actually killing someone. So I wish people would stop talking like that, avoid making that kind of argument.

@ChrisW My intention here is to remove any doubt that suicide is a wrong, flawed thing. If we are confident it is, then why not discuss it openly rather than run away from it and let doubt remain in the minds of people who may be too afraid to talk about it. Please don't take the investigation of death here to mean arguing for it.

@avatarKorra Maybe you're confident but I've answered several questions about suicide on this site, and the fact that people ask such questions is a bit worrying. So I don't like seeing casually ask, "So why don't you commit suicide then, to end suffering?" even if you only mean it as a rhetorical question and didn't intend it as a serious suggestion.

Why buddha teach rebirth?
Because highest goal of buddhism is to avoid rebirth.
In reality even buddha teach or doesn’t,
Rebirth mechanism is still there.
And it’s the origin of every suffer.

I've decided to create a second answer for this question, that's completely different to the first one.
Please also see this answer.
TL;DR
Denying rebirth-of-self view while clinging to self view is wrong view, because this is annihilationism and brings the unenlightened to hedonism.
Denying rebirth-of-self view after discarding self view is the noble right view. Rebirth without self view is simply the continuation of suffering and the continuation of the chain of conditioned processes. It's not about the rebirth of a specific person or being or self or consciousness.
Rebirth view can be used as skillful means (upaya) to remove the habit of misconduct, cultivate virtue and generate the path to liberation. Rebirth view is the middle way and is the right view with effluents/ taints.
Long answer
Denying rebirth-of-self, while clinging to self-view, appears to be wrong view. This is unskillful means because it directs the mind of the unenlightened towards hedonism and nihilism. This is also the view of annihilationism.

And what is wrong view? 'There is nothing given, nothing offered,
nothing sacrificed. There is no fruit or result of good or bad
actions. There is no this world, no next world, no mother, no father,
no spontaneously reborn beings; no contemplatives or brahmans who,
faring rightly & practicing rightly, proclaim this world & the next
after having directly known & realized it for themselves.' This is
wrong view.
MN 117

Holding on to the rebirth-of-self, while clinging to the fetter of self view, is a right view with effluents/ taints.

"And what is the right view with effluents, siding with merit,
resulting in acquisitions? 'There is what is given, what is offered,
what is sacrificed. There are fruits & results of good & bad actions.
There is this world & the next world. There is mother & father. There
are spontaneously reborn beings; there are contemplatives & brahmans
who, faring rightly & practicing rightly, proclaim this world & the
next after having directly known & realized it for themselves.' This
is the right view with effluents, siding with merit, resulting in
acquisitions.
MN 117

Why is this the case? This is because siding with merit, one could use this as skillful means (upaya), a helpful tool, to remove the habit of misconduct, cultivate virtue and generate the path to liberation.
The Buddha is the doctor (Iti 100) who treats the illness which is suffering (dukkha). This is a medicine that he has prescribed.

“And for the sake of what benefit should a woman or a man, a
householder or one gone forth, often reflect thus: ‘I am the owner of
my kamma, the heir of my kamma; I have kamma as my origin, kamma as my
relative, kamma as my resort; I will be the heir of whatever kamma,
good or bad, that I do’? People engage in misconduct by body, speech,
and mind. But when one often reflects upon this theme, such misconduct
is either completely abandoned or diminished. It is for the sake of
this benefit that a woman or a man, a householder or one gone forth,
should often reflect thus: ‘I am the owner of my kamma, the heir of my
kamma; I have kamma as my origin, kamma as my relative, kamma as my
resort; I will be the heir of whatever kamma, good or bad, that I do.’
.....
“This noble disciple reflects thus: ‘I am not the only one who is the
owner of one’s kamma, the heir of one’s kamma; who has kamma as one’s
origin, kamma as one’s relative, kamma as one’s resort; who will be
the heir of whatever kamma, good or bad, that one does. All beings
that come and go, that pass away and undergo rebirth, are owners of
their kamma, heirs of their kamma; all have kamma as their origin,
kamma as their relative, kamma as their resort; all will be heirs of
whatever kamma, good or bad, that they do.’ As he often reflects on
this theme, the path is generated. He pursues this path, develops it,
and cultivates it. As he does so, the fetters are entirely abandoned
and the underlying tendencies are uprooted.
AN 5.57

Once self-view is discarded, rebirth-of-self view will also be discarded. This is the noble Right View.

"And what is the right view that is noble, without effluents,
transcendent, a factor of the path? The discernment, the faculty of
discernment, the strength of discernment, analysis of qualities as a
factor for awakening, the path factor of right view in one developing
the noble path whose mind is noble, whose mind is without effluents,
who is fully possessed of the noble path. This is the right view that
is noble, without effluents, transcendent, a factor of the path.
MN 117

How do we know that rebirth-of-self view will be discarded? This is the higher teaching for those who have understood anatta, as taught in MN 38 and SN 22.85.
Rebirth without self view is simply the continuation of suffering and the continuation of the chain of conditioned processes. It's not about the rebirth of a specific person or being or self or consciousness.

“Yes, friend,” he replied, and he went to the Blessed One, and after
paying homage to him, sat down at one side. The Blessed One then asked
him: “Sāti, is it true that the following pernicious view has arisen
in you: ‘As I understand the Dhamma taught by the Blessed One, it is
this same consciousness that runs and wanders through the round of
rebirths, not another’?”
“Exactly so, venerable sir. As I understand the Dhamma taught by the
Blessed One, it is this same consciousness that runs and wanders
through the round of rebirths, not another.”
“What is that consciousness, Sāti?”
“Venerable sir, it is that which speaks and feels and experiences here
and there the result of good and bad actions.”
“Misguided man, to whom have you ever known me to teach the Dhamma in
that way? Misguided man, have I not stated in many ways consciousness
to be dependently arisen, since without a condition there is no
origination of consciousness? But you, misguided man, have
misrepresented us by your wrong grasp and injured yourself and stored
up much demerit; for this will lead to your harm and suffering for a
long time.”
MN 38

“But, friend, when the Tathagata is not apprehended by you as real and
actual here in this very life, is it fitting for you to declare: ‘As I
understand the Dhamma taught by the Blessed One, a bhikkhu whose
taints are destroyed is annihilated and perishes with the breakup of
the body and does not exist after death’?”
“Formerly, friend Sāriputta, when I was ignorant, I did hold that
pernicious view, but now that I have heard this Dhamma teaching of the
Venerable Sāriputta I have abandoned that pernicious view and have
made the breakthrough to the Dhamma.”
“If, friend Yamaka, they were to ask you: ‘Friend Yamaka, when a
bhikkhu is an arahant, one whose taints are destroyed, what happens to
him with the breakup of the body, after death?’—being asked thus, what
would you answer?”
“If they were to ask me this, friend, I would answer thus: ‘Friends,
form is impermanent; what is impermanent is suffering; what is
suffering has ceased and passed away. Feeling … Perception …
Volitional formations … Consciousness is impermanent; what is
impermanent is suffering; what is suffering has ceased and passed
away.’ Being asked thus, friend, I would answer in such a way.”
SN 22.85

Why now do you assume 'a being'?
Mara, have you grasped a view?
This is a heap of sheer constructions:
Here no being is found.
Just as, with an assemblage of parts,
The word 'chariot' is used,
So, when the aggregates are present,
There's the convention 'a being.'
It's only suffering that comes to be,
Suffering that stands and falls away.
Nothing but suffering comes to be,
Nothing but suffering ceases.
SN 5.10

"Then, Bāhiya, you should train yourself thus: In reference to the
seen, there will be only the seen. In reference to the heard, only the
heard. In reference to the sensed, only the sensed. In reference to
the cognized, only the cognized. That is how you should train
yourself. When for you there will be only the seen in reference to the
seen, only the heard in reference to the heard, only the sensed in
reference to the sensed, only the cognized in reference to the
cognized, then, Bāhiya, there is no you in connection with that. When
there is no you in connection with that, there is no you there. When
there is no you there, you are neither here nor yonder nor between the
two. This, just this, is the end of stress (suffering)."
Ud 1.10

I think this is excellent because it finally tells us what rebirth really is in Buddhism. It's not falsehood. It's not truth. It's just skillful means (upaya), a helpful tool. A middle way between falsehood and truth.

what do you say if asked whether a stream-enterer exists after death?

@Letsbuddhism The answer to this question, from the perspective of ultimate truth comes from Yamaka Sutta and Vajira Sutta. - "What? Do you assume a 'living being,' Mara?
Do you take a position? This is purely a pile of fabrications. Here no living being can be pinned down."

then i say, in as far as having grasped with wrong view something to be a stream-enterer then, is this stream-enterer said/held/seen to take another birth in particular?

@Letsbuddhism A stream enterer has discarded self-view. Which wrong view is grasped? A stream enterer is a person (puggala) as stated in Bhara Sutta (SN 22.22). But this is also a fabrication. The first noble truth says "there is suffering". It doesn't say "there is a sufferer".

i mean that it is said that a sotapanna won't take an 8th birth. It is said in regards to what is said to be a being, a being a concept that is conceived due to a grasping what the senses present with wrong view. Therein mind or body are misunderstood and taken to be personal and or eternal. This is the doctrine of self, in this doctrine of self one speaks of rebirth of a being. Having abandoned wrong view one can still entertain and understand the doctrine without believing it.

If they don’t penetrate so far, with the ending of three fetters, they’re a one-seeder. They will be reborn just one time in a human existence, then make an end of suffering.
If they don’t penetrate so far, with the ending of three fetters, they go from family to family. They will transmigrate between two or three families and then make an end of suffering.
If they don’t penetrate so far, with the ending of three fetters, they have at most seven rebirths. They will transmigrate at most seven times among gods and humans and then make an end of suffering.

obviously the answer as to whether a sotapanna is reborn is yes and that up to seven times and the answer as to whether sotapanna can be pinned down as a truth & reality in & by itself is a no. However there is that which can be grasped with wrong view to be a sotapanna and that will change as it persists until it is fully extinguished in no more than 7 births.

@Letsbuddhism Yes, that's right.

I think it's not a problem to say that a sotapanna exists after death in as far as they are held to transmigate for up to seven more times and that only Arahants in this exact sense abandon all modes of existence in as far as they become completely extinguished with no residue for a future. I like both of your answers.

also this then makes sense 'Having understood the unconditioned state,
Released in mind with the cord of being destroyed,
They have attained to the Dhamma-essence.
Delighting in the destruction (of craving),
Those stable ones have abandoned all being.'

@Letsbuddhism The idea of rebirth without self view is simply the continuation of suffering and the continuation of the chain of conditioned processes. It's not about the rebirth of a specific person or being or self or consciousness

This seems very wrong. I think your previous answer was better ;)

@YesheTenley The previous answer is tainted with self view.

This one too, but with more confusion as a spice :)

@YesheTenley At some point, we have to stop sneaking in the self through the back door.  ;-)

Who is this "we" you refer to? Do you and I not exist?

@YesheTenley That's Mara.

Was it Mara speaking to Ananda in MN 81? "Ānanda, you might think: ‘Surely the brahmin student Jotipāla must have been someone else at that time?’ But you should not see it like this. I myself was the student Jotipāla at that time.”

You've misunderstood Vajira and should put down that snake you are grasping.

@Ruben2020 by suffering therein what exactly do you mean? I am trying to make sure nothing slips by and it is close as it is but depends on what you mean by suffering, if you mean sankhara-dukkhata denoting anything other than the nibbana principle then i would agree with the expression

@Letsbuddhism Yes, that's right.

@YesheTenley I have added Bahiya Sutta (Ud 1.10). That should be very clear.

That is a wonderful sutta, but in no way denies the rebirth of persons. For such a mind unbound a 'person' does not even appear. What could there be to deny?

We are lucky, we are most fortunate to find in you, friend, a companion in the holy life who is so well-versed in both the meaning and the expression!

Rebirth Concept was there in India[Early stages India called Dambadiwa] among Rishi's who meditated and achieved "Dyana" supreme mental states.  Actually,  Buddha taught us how to stop rebirth. This is the concept Lord Buddha understood from his Omniscience. Though the rebirth concept was there even "Rishi" did not have Supreme mundane wisdom to explain rebirth concept exactly.  They might have seen previous births in some extend where lord buddha seen rebirth to the eternity. That is why his wisdom called Omniscience.
Why do we wanted to avoid pain of Cancer? Because it causes whole life suffering. By knowing that we are taking precautionary measures to avoid cancer. If we found it earlier stages we completely remove it from the body. Furthermore, to avoid occuring cancer cells we do chemotherapy.
Similarly, Lord Buddha understood from his Omniscience that the creatures are sufferings from eternal journey of samsara within this 31 levels of the universe [4 Hells, 26 Divines and Earth].  Out of these 31 most of the creatures travelling through 4 hells only. Very similar to the cancer.
Giving this example he said. If someone takes a certain amount of soil from the earth on the nail tip of the thumb finger, that much creatures  will go to the divine worlds , the Brahma worlds  and  the human world,. Rest of the creatures equal to the earth's soil will go to hell. That is why Lord Buddha introduce  the hells  as creature's great house.
By knowing this great disaster with "Metta and Karuna" he wanted to stop creatures facing this agony while rescuing them.
Without convincing the reality of this samsara journey, the painful sorrowful agony one can face and going through, if he talk about the luxury life then no one wanted to attain Nibbana.  People love this lust life.
Lord Buddha in his Omniscience understood the way to overcome this dependent origination circle  by stopping the rebirth. That is where he introduce us four noble truth and the eightfold path.
Now your question was answered.  Without knowing the cause or the reason we cannot overcome the issue.  We need to stop occurrence to stop the result occurring due to that cause.
That is why causality was explained.
May Triple Gem Blessed You.

The Buddha taught rebirth because it is something real that is related to the arising of suffering; namely, the re-arising of the delusion of "self" as a result of the emotions created by kamma (actions). Whenever the idea of "I" or "mine" arises as a result of an action, this is "rebirth".
Discerning an absence of rebirth in the mind is necessary to understand emptiness. Also, rebirth (kamma & results) is one example of causality.
A Buddhist doctrine that make sense without rebirth is the Three Characteristics. Seeing the Three Characteristics is unrelated to rebirth.
Knowing Nirvana is also unrelated to rebirth although, similar to Emptiness, knowing Nirvana coincides with knowing an absence of rebirth in the mind.
As for a rebirth as an "afterlife", this is an unknowable unproveable primitive superstition. Any claims there is a "Truth of Afterlife Rebirth" is obviously a lie or falsehood because there is no evidence for this belief. It is only a "belief" but not a "truth".

"obviously a lie or falsehood" is problematic and I think you should remove this. It is disparaging others and impolite and does not reflect patience for others understanding even if you think that "understanding" is a misunderstanding or confusion.

Thinking that all mental activities end at death is the unsubstantiated, unskillful, primitive, superstitious belief. :)

Read my answer.


text:
Does SN44.9 imply an intermediate state between births?
According to Kutuhalasala Sutta (SN44.9), translated by Thanissaro Bhikkhu:

Vacchagotta: "And at the moment when a being sets this body aside and is not yet reborn in another body, what do you designate as its
  sustenance then?"
Buddha: "Vaccha, when a being sets this body aside and is not yet reborn in another body, I designate it as craving-sustained, for
  craving is its sustenance at that time."

Alternative translation by Bhikkhu Bodhi here:

Vacchagotta: “And, Master Gotama, when a being has laid down this body but has not yet been reborn in another body, what does Master
  Gotama declare to be its fuel on that occasion?”
Buddha: “When, Vaccha, a being has laid down this body but has not yet been reborn in another body, I declare that it is fuelled by
  craving. For on that occasion craving is its fuel.”

In the Theravada tradition, the orthodox doctrine based on the Abhidhamma states that there is no intermediate state between births, that rebirth-linking consciousness instantaneously results in a new birth without any gaps.
However, the above sutta implies that it is possible to have an intermediate state that is sustained by craving.
So, my question is: does SN44.9 imply an intermediate state between births, or is there an alternative interpretation for it?

Piya Tan has an essay on the topic here: Is Rebirth Immediate? (SD 2.17)
And a commentary and translation of the sutta here, Kutūhala,sālā Sutta, which includes "To Vaccha’s second and final question, the Buddha makes his famous statement on the intermediate state."
My paraphrase of the essay (if I've read it correctly) is that:

The Abhidhamma and commentaries denies an intermediate state, on not very strong grounds (e.g. that the Buddha didn't teach explicitly that there is such a thing)
Many people (Theravada and other schools) believe in such a state anyway
There are suttas (which it quotes) which may be describing an intermediate state
Other sources include the Chinese Agamas, and the Sanskrit, the Milinda Panha

That essay totals about 15 pages -- you can read the details.
It quotes Ven. Sujato's commentary on The Kutūhala,sāla Sutta:

From this we can conclude that the Buddha, following ideas current in his time—for Vacchagotta
  was a non-Buddhist wanderer (paribbājaka)—accepted that there was some kind of interval
  between one life and the next. During this time, when one has “laid down” this body, but is not
  yet reborn in another, one is sustained by craving, like a flame tossed by the wind is sustained by
  air. The simile suggests, perhaps, that the interval is a short one; but the purpose of the simile is to
  illustrate the dependent nature of the period, not the length of time it takes. While a fire is burning
  normally, it is sustained by a complex of factors, such as fuel, oxygen, and heat. But when a
  tongue of flame is momentarily tossed away from the source fire, it can last only a short while,
  and in that time it is tenuously sustained by the continued supply of oxygen. Similarly in our
  lives, we are sustained by food, sense stimulus, and so on, but in the in-between, it is only the
  slender thread of craving that propels us forward. The difference is, of course, that the flame will
  easily go out, while the fuel of craving propels the unawakened inexorably into future rebirth.

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text:
Why have I awoken Now?
I am riddled by this question lately and it necessary for my progress on path of Dhamma. My question is, why is it that in this life time I have became obsessively bent to attain nibbana while everyone around me is living in total oblivion. I mean if I had so many rebirths in past lives exactly what was I doing all these quantillion lives, was I never told the dhamma. If I was told, then why am I not already enlightened. Was I dumb or something all these lives not to have awaken to the truth of suffering? What must have been my mistake all these lives? How can I rectify that mistake so that I can felicitate my nibbana in this life?

-- "why is it that in this life time I have became obsessively bent to attain nibbana"
There is a traditional Buddhist teaching that explains this Awakening through a combination of lucky causes and conditions. When the conditions are unlucky, they are known as "Eight Conditions in Which There is No Freedom to Practice Dharma". When the conditions are lucky, there are known as "The Ten Advantages" or "The Five Individual and Five Circumstantial Advantages". I will not quote them here verbatim, for fear of simplistic reification - instead I will try to explain the idea behind it.
Awakening happens when your life conditions are "just right". Being "just right" means they are not too bad but not too "worldly good" either.
On one hand, there has to be enough good luck to be born in the right place at the right time to encounter Dharma, and your personal circumstances should be good enough to allow you to pay attention to it. Meaning, you need to be born in the right historical period in a civilized country that has Dharma available in some form, when there is no active war or other issues that would completely distract from anything but survival. You also have to be born a human or other type of sentient being that has its mental faculty in a good functional order.
On the other hand, you need to have enough suffering in your life and enough confusion to push you to seek some sort of resolution. If your life circumstances are too structured from birth, for example you are born to a family that has everything running well and under control, you may be so completely preoccupied with worldly activities of study, work, art, making business etc., that you will have zero interest in Dharma even if the Buddha himself were to teach you.
Just enough suffering and confusion -- but not too much -- because too much suffering and confusion leads to perverted worldviews, excessive aggression, extreme pessimism/hopelessness/nihilism, an idea that one can only get happy by abusing others, incurable cynicism, addictions etc.
So when these multiple "just right" causes and conditions come together all at the same time, we have this phenomena of Awakening - one day you come in touch with Dharma and you are interested. This is the moment when your negative seeds (suffering, confusion) and your positive seeds (open mind, intuitively right values) germinate in the ground of lucky circumstances.
This combination of positive and negative factors is very important. This is why human condition is so valuable, compared to other life forms. It gives just enough positive and negative factors in just the right proportions. It does not happen all the time, true, but still a million times more frequently than with almost any other type of sentient life. We are lucky to be messed up just enough to Awaken! :))
-- "Why am I not already enlightened? What must have been my mistake all these lives? How can I rectify that?
As you can imagine, there's any number of mistakes you could have made, but here is one traditional list, known as "The Eight Intrusive Circumstances". I will list them here in brief, it could be one or more in your case:

you failed to overcome negative emotions dominating your mind.
you were intellectually lazy and did not want to make effort to study Dharma.
you failed to identify a confused teacher as such, and wasted your chance by following incorrect teaching.
you were a procrastinator when it came to meditation.
you failed to cut the self-perpetuating cycle of negative karma, and it claimed your freedom back.
you did not say "no" to worldly people in your life that wanted you to do what they thought was important.
you always prioritized solving your worldly problems over Dharma.
you fell victim to the temptation of using Dharma as a source of money, power, or fame - and lost connection with genuine virtue.

I'm sure there are countless other potential mistakes one could have made, but this should get you started. There is much more on this topic in a book I recommend, "The Words of My Perfect Teacher" by Patrul Rinpoche.

You've been here since forever due to craving and ignorance.
Ignorance of not knowing the Four Noble Truths.
There are 3 types of craving - sensual, becoming and unbecoming.
Basically, you're here because you deeply want to be here, you want to enjoy sensual pleasures, you want to become somebody, you want to live a full happy life and you did not know about the Four Noble Truths till the "man with good eyesight standing on the river bank" told you. There's no need to blame Mara or anyone else.
You're here because you craved to be here.
From Itivuttaka 114:

This was said by the Blessed One, said by the Arahant, so I have
  heard: "Suppose a man was being carried along by the flow of a river,
  lovely & alluring. And then another man with good eyesight, standing
  on the bank, on seeing him would say: 'My good man, even though you
  are being carried along by the flow of a river, lovely & alluring,
  further down from here is a pool with waves & whirlpools, with
  monsters & demons. On reaching that pool you will suffer death or
  death-like pain.' Then the first man, on hearing the words of the
  second man, would make an effort with his hands & feet to go against
  the flow.
"I have given you this simile to illustrate a meaning. The meaning is
  this: the flow of the river stands for craving. Lovely & alluring
  stands for the six internal sense-media. The pool further down stands
  for the five lower fetters. The waves stand for anger & distress. The
  whirlpools stand for the five strings of sensuality. The monsters &
  demons stand for the opposite sex. Against the flow stands for
  renunciation. Making an effort with hands & feet stands for the
  arousing of persistence. The man with good eyesight standing on the
  bank stands for the Tathagata, worthy & rightly self-awakened."

The conditions and the reasons why sb chooses to follow the path of enlightenment in one lifetime are not clear.
To say that your Karma is wright,what about Milarepa who in one lifetime killed people?And at the same time he gained liberation.
Then Retchung asked, 'O lama, you spoke of having done white deeds, and no deeds are worthier than those devoted to the Dharma. How, Master, did you first encounter the teaching?' And the Venerable One continued thus:

I was filled with remorse for the evil I had done by magic and by
  hailstorms. My longing for the teaching so obsessed me that I forgot
  to eat. If I went out, I wanted to stay in. If I stayed in, I wanted
  to go out. At night sleep escaped me. I dared not confess my sadness
  to the lama or my longing for liberation. While I remained in the
  lama's service, I asked myself unceasingly and passionately by what
  means I might practice the true teaching.The lama replied, 'All sentient beings have the Buddha-nature within them. I know theoretically how to lead them to higher realms and liberation, but when conditions arise which test my actual attainment, I only remember words and ideas. I have no confidence in my ability to help beings. But now I am going to practice the Dharma to be able to meet any circumstances that arise. Either you must take over the guidance of my disciples so that I can devote myself to the practice leading to the higher realms and liberation, or you must practice the Dharma yourself and help us all achieve the higher realms and liberation. Meanwhile I shall support you with all the provisions you need.'

Thus my wish was fulfilled and I answered that I would practice the Dharma myself.

Tilopa

He first became a monk at the temple of Somapuri in Bengal. It is said
  that one day a dakini (female embodiment of wisdom) came to him in a
  vision and offered him her knowledge. Tilopa requested her teachings
  and received the initiation into the Chakrasamvara Tantra.

Naropa

Naropa went to the house of a woman who sold beer and encountered a
  junior Buddhist pandita. After the Buddhist pandita departed, Naropa
  found a volume of Sutras left behind by him and began to read them. He
  became very inspired by the teachings and his heart filled with
  devotion for the dharma.

There is no such thing as "past lives". Please read SN 22.79, which explains clearly the meaning of "past nivasa". If there were past lives, we would be born into this world with much wisdom, knowledge & experience.

Of course there are past and future lives! Don't you know other humans existed before us and will exist after us? ;)

I am riddled by this question lately and it necessary for my progress on path of Dhamma. My question is, why is it that in this life time I have became obsessively bent to attain nibbana while everyone around me is living in total oblivion.
Society is by and large enslaved by Mara the evil one. This answer explains in detail. Don't go by the society.
I mean if I had so many rebirths in past lives exactly what was I doing all these quantillion lives, was I never told the dhamma. If I was told, then why am I not already enlightened. Was I dumb or something all these lives not to have awaken to the truth of suffering?
You were and are under the influence of Mara as is almost everyone. Do you think Steve Jobs was dumb , Bill Gates is dumb or Einstein was dumb ? No. Even the smartest of people fail to get the insight.
What must have been my mistake all these lives? How can I rectify that mistake so that I can felicitate my nibbana in this life?
Yours and everyone's mistake is that they haven't renounced the self and the world. They still think that the eyes is theirs. They still still think ears is theirs. They still think body is theirs. They still think Mind is theirs. When in actuality it all belongs to Mara. To rectify the mistake ,I guess the best way would be to, renounce the world and walk the path which Buddha laid.

Dheeraj  thanks for answering... I know who is mara from buddhist scriptures but it doesnt practically make sense to blame Mara. I mean, i dont actually believe that there is some evil being in reality named Mara who is bothering us all...I mean what personal interest will he have in my life...this must be some sort of allegory...what exactly is Mara? So that leaves my question unanswered. Sorry for being so pedantic...

@BodhiWalker I have quoted from the scriptures. It is not possible to believe in Buddha and not believe in Mara. Mara rules the world which Buddha wants you to renounce.

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text:
What is Aarya Upavaada?
Based on a real situation, I have come across some people who claim to be Sotapanna and Sakadaagaami.. When i have gotten angry or upset about something they said or did, i was told i am committing Aarya Upavaada. This is nothing to do with Dhamma but personal issues such as relationships and finances. I am told if i get angry or upset with them, i am still committing Aarya Upavaada as the people involved are Aarya.
With Sutta references, could someone tell me if this is indeed Aarya Upavaada and what actually constitutes Aarya Upavaada?

Dear Gaveshika… if those people that you have come across are the type that tells any Tom, Dick or Harry that they meet that they are Sotapanna and Sakadaagaami, then you have nothing to fear. Only to such a person who has similar characteristics (gathi) as him/her, would a Sotapanna reveal that he/she is one such. By that what I mean is that, if an ordinary run-of-the-mill person asks you whether you a Sotapanna, you will evade that question, as this knowledge is something that you keep very close to your heart. So no fear, you have not committed an Aarya Upavaada.
But in case you had (even inadvertently) done a Aarya Upavaada to someone who walks this Noble Path that day, you could think about that person and ask for forgiveness. This is a very effective way to calm the mind and reduce tensions. If done sincerely, you should be able to see the effects in real life. You may notice that the tensions with that person is automatically reduced.
..........
A person who treads this Path in all sincerity knows at every stage where s/he is at.  One realizes that one is a Sotapanna, but it happens with time. When one observes oneself, it becomes clear to oneself that one has removed the characteristics (gathi) that prevents one from becoming such, and that you have attained that precious thing/stage sought by a Bhauddhaya (or a practicing Buddhist). Also, when you observe such characteristics (gathi) in a another (be it a much sought-after monk) you begin to question as to how that person could even be a Sotapanna. But you guard yourself and do not entertain such thoughts, as only a Buddha can say for sure whether a given person other than you, has attained magga phala or not. In this Path you will ONLY concern about yourself and NOT any other.
At this stage you do not need any guidance from another. You have seen the way to Nibbana (or a glimpse of Nibbana). You know what’s to be done, and silently you go about it, and your neighbours and others that you come across in your daily life will never know that you are one such (a Sotapanna). Once that knowledge that you have arrived at this stage of Sotapanna sinks in, your attitude, behavior, and outlook on life has changed forever.
Observing another person’s characteristics (gathi), you then get a feeling that there is a greater likelihood that the other person is at the Sotapanna stage or higher. ONLY with such a person would you share this kind of knowledge.

Thank you. Both persons I refer to, tell people they are "Aarya" and "Maarga Pala Laabhi", even if such people are not ones with similar gathi. Thank you for your insight.

May be I will try to expand on what I said above, for you to better understand the 'Gathi' of a Sotapanna.  - with metta.

0.0. Talking, speech, blaming, teaching with any 5 hindrances could be 5 Cetokhila. Actually, all of them are the barrier of enlightenment, not only blaming by anger.
0.1. We shouldn't angry anyone, even though that one is not ariya. And we can't know the truth exactly  if we have no 8 vijja skills (8 genuine awarenesses), so it is very easy to distort the truth, wrong speech. Be quiet is easier than undo spoken speech.
0.2. Upavada is blaming by angry. See Sutta. Aṅ. (2): catukkanipāto
Bhayavaggo tatiyo
[121]   Attānuvādasuttaṃ  .

The blaming can done by a wholesome mind, such as the blaming  when Buddha created each vinaya rule, or by an unwholesome mind, such as ariya-upavada.
That unwholesome mind of upavada can take 2 object types:  wrong condition object of under sotapanna's, and  right condition object, sotapanna's and sakadagami's mind.

2.1. Example of wrong condition object: Under sotapanna blame an arahanta-bhikkhu  "you are immoral (because you make love with a lady)". This case is fail, because arahanta doesn't has caving left to making love, except raped or sleeping.
2.2. Example of right condition object: the sotapanna blame an arahanta-bhikkhu  "you are immoral (because you let your tear wet the Buddha's foots)". This case can be right because tearing Buddha's foots is not a good action, however if that sotapanna blame by unwholesome mind, angry, it is upavada.

Upavada is rooted in anger or Patigha which is a unwholesome or akusala mental formation or chayithasika with  unwholesome results or vipaka whether you commit the act verbally, physically or mentally to an Aarya or non-Aarya person. Of course done to an Aarya is more grievous especially done to an Arhath or The Buddha.
Only the Buddha has proclaimed himself(Sinhanada sutta)to be Fully Enlightened without being asked.Often it is the Buddha who  announces that such and such desciple is now achieved Arahant status. IMHO any one who brags that he/she is Sotapanna is a  charlatan!

People are egotistical, have delusions of grandeur, and use religion (Buddhism, Christianity, Islam, it doesn't matter which one) to reinforce their delusions of grandeur. If someone is showing obvious signs of being offended easily by having their claims questioned, if they show egotism, claiming that you disagreeing with them is tantamount to disagreeing with the Buddha himself, then they are clearly not a stream-entrant. It isn't your job to convince them that they are not. Likely, no one could. Don't worry yourself over narcissists on the Internet. My advice.


text:
Why walking meditation is not mentioned in the ways of attending to mindfulness?
Namo Buddhaya.
Buddha talks about walking meditation at several places in the suttas for example here. However he doesn't mention it in the Long discourse about the ways of attending to mindfulness. There are 4 ways of attending to mindfulness but none of them mention walking or walking meditation.
My questions are :
Why doesn't Buddha mention about the walking or walking meditation in the long discourse about the ways of attending to mindfulness?
Is there any sutta where Buddha talks about the technique of walking meditation?

I think that walking is mentioned in DN 22 -- in the translation you referenced, it is this:

Moreover, monks, a monk while going knows “I go”; or, standing he knows “I am standing”; or, sitting he knows “I am sitting”; or, while lying down he knows “I am lying down”; or, in whatever way his body is disposed, he knows it is (disposed) in that way.

Ven. Sujato's translation:

Furthermore, when a mendicant is walking they know: ‘I am walking.’ When standing they know: ‘I am standing.’ When sitting they know: ‘I am sitting.’ And when lying down they know: ‘I am lying down.’
  Whatever posture their body is in, they know it.


text:
Is "the mind is without feature or surface, limitless, ..." in the Pali canon?
in John Haspel's book, 'Becoming Buddha', the following quote is attributed to MN 11:

“Magandiya, when you hear the true Dhamma, ... When released from
clinging the mind is without feature or surface, limitless, outside of
time and space, freed from the six-sense base.”

Here's a larger quote:

While meditating with tranquility, allow insight to arise and have a direct experience of the Buddha’s teachings leading to abandoning clinging and the cessation of suffering. Experience awakening through unbinding the Five Clinging-Aggregates.

“Magandiya, when you hear the true Dhamma, you will practice the Dhamma correctly. When you practice the Dhamma correctly, you will know & see for yourself: ‘This is where confusion and suffering ceases without trace. With the cessation of my clinging comes the cessation of becoming. With the cessation of becoming comes the cessation of birth. With the cessation of birth then aging & death, sorrow, lamentation, pain, distress, & despair all cease. Such is the cessation of this entire mass of suffering & stress.” (Majjhima Nikaya 11)

The Buddha describes a mind free of clinging and freed of association to the five clinging aggregates:

“released from clinging the mind is without feature or surface, limitless, outside of time and space, freed from the six-sense base.” (Majjhima Nikaya 11)

(This text was copied from Becoming-Buddha.com. If you found this helpful, please visit our website for more Dhamma articles. All content is copyright 2017 by John Haspel and is distributed under a Creative Commons 4.0 license. Here is a link to the full article: The Five Clinging Aggregates | Becoming Buddha)

However I don't see this phrase, that verse about the nature of the mind, in translations of MN 11.
Because the quote mentions Magandiya, I looked in MN 75 as well, but don't see it there either.
Is that verse anywhere to be found in the Pali Canon?
Thanks for your much appreciated help.

There's a similar phrase (not an exact match) in DN 11:

This is how the question should be asked:
  Evañca kho eso, bhikkhu, pañho pucchitabbo:
85.11 “Where do water and earth,
  ‘Kattha āpo ca pathavī,
85.12 fire and air find no footing;
  tejo vāyo na gādhati;
85.13 where do long and short,
  Kattha dīghañca rassañca,
85.14 fine and coarse, beautiful and ugly;
  aṇuṃ thūlaṃ subhāsubhaṃ;
85.15 where do name and form
  Kattha nāmañca rūpañca,
85.16 cease with nothing left over?”
  asesaṃ uparujjhatī’ti.
85.17 And the answer to that is:
  Tatra veyyākaraṇaṃ bhavati:
85.18 “Consciousness that’s invisible,
  ‘Viññāṇaṃ anidassanaṃ,
85.19 infinite, radiant all round.
  anantaṃ sabbatopabhaṃ;

Maybe that it's it: if MN 11 was mistaken for DN 11; but it's not an exact match.
Even so I think that may be the Pali phrase you're looking for --

Viññāṇaṃ anidassanaṃ, anantaṃ sabbatopabhaṃ

For example this (The Four Noble Truths and Noble Eightfold Path) translates these words as:

Nirvana is a realm where corporeality and all the pairs of opposites - long and short, great and small, pure and impure - disappears and the mind is signless (anidassanam), boundless (anantam) and all-radiant (sabbato pabhamn). It is unchanging state (nibbanam accutam) of purity (suddhi), freedom (vimitti)  and  supreme happiness  (nibbanam paramam sukham).

... although that doesn't say which sutta[s] these words come from.
Another place that phrase appears is in MN 49 (but also not an exact match, i.e. "freed from the six-sense base" isn't part of the phrase there).


text:
In breathing mindfulness ,why only long and short breaths are taken into consideration?
I have just started practicing breathing mindfulness.
At several places following is said for the breathing mindfulness:

While breathing in long, he knows “I am breathing in long”, or, while
  breathing out long, he knows “I am breathing out long”; or, while
  breathing in short, he knows “I am breathing in short”, or, while
  breathing out short, he knows “I am breathing out short”.

However most of the time I am breathing normally. I am neither taking long breath nor short breath.
My question is: Why normal breathing situation is ignored during breathing mindfulness? In other words ,why don't we say "While breathing in normal , he knows 'I am breathing in normal', or , while breathing out normal, he knows ' I am breathing out normal'"?

Please untick my answer to your question because I wish to delete it. Thank you.

I can guarantee that you can take normal breathing. And you should take normal breath. Without trying to make it long or short.

While breathing in long, he knows “I am breathing in long”, or, while breathing out long, he knows “I am breathing out long”; or, while breathing in short, he knows “I am breathing in short”, or, while breathing out short, he knows “I am breathing out short”.

As you state, Normal breathing is not ignored but it just a way to teach meditators.
The goal of this sentence is you should know every single moment of breath.

If the mind has right mindfulness (which is a quiet mind due to keeping the mind free from craving), it will naturally & automatically become aware of the breathing. This being aware of the breathing (with mindful equinimity) will cause the breath to calm. In this calming process, the breathing will become longer. However, when stored internal stress is touched, the breathing will become short until the stress is calmed & dissolved. Therefore in the proper practise of Anapanasati, the breathing will be both long & short (even though the calming process inclines to long breathing). For example, a normal long in-breath causes the abdomen to expand. However, an extra long very calm & refined in-breath will first cause the abdomen to slightly expand but then mostly contract.
The first two (preliminary) stages Anapanasati are merely descriptions of what the mind should be aware of when it has right mindfulness. To know a breath that is long and to know a breath that is short shows the mind has discernment, clarity, sensitivity & right mindfulness.

MANY KINDS OF BREATH
While we practice following, we have the opportunity to observe
  various characteristics of the breath. We can feel many things, For
  example, we can feel the longness and the shortness of the breath. We
  naturally learn about the long breath and short breath. Then we
  observe the coarseness and fineness of the breath. Further, we observe
  its smoothness and burnpiness. Later, we will observe the [physical & mental] reaction to
  these qualities. In this first step contemplate these different kinds
  of breath: long and short, coarse and fine, easy and uneasy. Begin to
  observe them by feeling them with sati. (51)
We must learn how to observe in more detail, that is, to observe the
  reaction or influence of the different kinds of breathing. What
  reactions do they cause, how do they influence our awareness? For
  example, when the breathing is long, how does it influence our
  awareness. What reactions does the short breathing cause? What are the
  influences of coarse and fine breathing, comfortable and uncomfortable
  breathing? We observe the different types of breath and their
  different influences until we can distinguish clearly how the long and
  short breaths, coarse and fine breaths, and comfortable and uncomfortable breaths differ . We must know the variations in the
  reactions to and influences of these various properties of the breath,
  of these qualities that influence our awareness, our sensitivity, our
  mind. (52)
Along with the above observations, we need to watch the effect or
  flavor of the different kinds of breath. The flavors that arise are
  kinds of feelings, such as, happiness, non-happiness, dukkha,
  annoyance, and contentment. Observe and experience the flavors or
  effects caused, especially, by the long breath and short breath, by
  the coarse breath and fine breath, and by the easy breath and uneasy
  breath. Find out how it is they have different flavors. For instance,
  we will see that the long breath gives a greater sense of peace and
  well being, it has a happier taste than the short breath. Different
  kinds of breath bring different kinds of happiness. We learn to
  analyze and distinguish the different flavors that come with the
  different kinds of breath that we have scrutinized. (53)
Finally, we will discover the various causes that make the breath
  either long or short. We gradually will find this out for and by
  ourselves. What causes the breathing to be long? What kind of mood
  makes the breath long? What kind of mood makes it short? Thus, we come
  to know the causes and conditions that make the breath long or short.
  (54)
Anapanasati

As I have learnt in S.N. Goenka's Vipassana course, you have to be aware of normal breath only. If you are not able to concentrate on breath in normal mode only then you make a forced breathing to be long or short.
So the normal is norm.

Why normal breathing situation is ignored during breathing mindfulness?

Normal breathing happens automatically,you are not aware of it!
Watch your breath!
The secret lies in the simple observance and bringing awareness and presence to the breath.This is one of the main teachings of the Buddha! The process of breathing in and out is not a parallel movement as one might think.
Between the in breath (down) and the out breath (up) and again between the out and in breaths there are gaps.Fear of losing identity causes a jump over the gap because "I" or "me" doesn’t exist there.


text:
Under what conditions should Buddhists proselytize other Buddhist traditions?
Under what conditions is it proper for Buddhists of one tradition to try and proselytize Buddhists from another tradition? Under what conditions is it improper? What harm can be done? What fruits can be gained?
Can cross-tradition debate be a good thing? Is it ever a bad thing? What is the proper motivation to do so? What are improper motivations? What is skillful? What is unskillful?
Is it desirable to grant a modicum of respect for all traditions? How should this respect be manifested? What are examples of disrespectful dialogue and how can/should the line be drawn?
Note: I'd prefer if these questions are not used to proselytize or engage in debate about Buddhist doctrine... but rather to answer the questions above.
... and references to dharma teachings, historical events, or opinions/literature of noted teachers also welcome and encouraged!

I have a feeling this is more of a meta question... Most of our questions expect answers that are informed either by scripture, or by personal studies under teachers, or by personal experience - but this is an invitation for an open-ended panel-style discussion. As such I don't think it makes it a good fit for this platform. Will be happy to hear other opinions and reopen.

Happy to move this to meta... would that make more sense? OTOH, maybe there is teachings on this?? For instance, the sanskrit tradition holds that many cross-tradition debates occurred throughout history that could potentially inform answers here. I was hoping maybe there would be real answers based on dharma.

@ChrisW what do you think?

@AndreiVolkov Move it to Meta, if you want to ask whether the community wants users to do that on this site. Or leave it here if the question isn't about "proselytising" on this site n particular. Or create a topic on Meta to discuss whether to reopen this question here and/or how to improve this question. If you leave it here and ask everyone "What's your opinion and experience?" that's OK but might be a polling question. You could (instead of or as well as asking for personal experience) also ask for references on the subject: "what essays/opinions have other people published on this topic?"

Question was more general and not just whether it should be done on this site. Question was inspired by the great conversation we had last night and another today.

"Proselytise" is defined as "attempt to convert". And "debate" sounds like it might be to try to decide which of the two sides of an argument is the winner. Is that what you're asking about? When conversation is mutually agreeable, isn't it usually called "interfaith dialog" (or something like that) instead: learning more, sharing views, comparing doctrines ... and maybe not trying to persuade nor disprove?

I read once that "debate" is a feature of Tibetan education, so you may have a different attitude towards it.

Yeah, I have tentative ideas of how I might define and answer these questions, but I want to hear what others think :) hence the questions :) although @tenzindorje would probably tell me I am silly for thinking I can “hear” what others think LOL

Alright, so I just dusted off a 2014 question about debates in Buddhism, cleaned it up a bit, and merged most of this question's points as follow-up to that. I suppose we could just reopen this question after rewording it slightly, but I figured it would be nice to reuse an existing question that already had some answers.

See also How are Buddhists supposed to spread Buddhism?


text:
What Nichiren Buddhism says about rebirth and reincarnation?
What is the view of Nichirenism/ Nichiren Buddhism on rebirth and reincarnation? What was the opinion of Nichiren on rebirth and reincarnation? What was the opinion of Gautama Buddha on rebirth and reincarnation according to Nichiren?

Do you have reason to believe it is different from other traditions/schools of Buddhism? If so, could you elucidate those reasons in your question?

Nichiren explains the Buddhist concepts of Twelve Linked Causation and Transmigration

On the Principle of Three Thousand Realms in a Single Moment of Life
"Question: What is the twelve-linked chain of causation as it applies to the process of transmigration?
Answer: The first link is ignorance. The Dharma Analysis Treasurysays: “The state resulting from past delusion is ignorance.” That is to say, ignorance represents the earthly desires of love and craving that one gave rise to in the past. Thus a son may conceive hatred for his father and love for his mother, or a daughter may conceive hatred for her mother and love for her father, as described in the ninth volume of Dharma Analysis Treasury.
The second link is action. Dharma Analysis Treasury says: “The various deeds carried out in the past are called action.” That is, the deeds or karma one has created in the past are called action. There are two kinds of karma. The first is “karma leading to rebirth,” that is, karma that determines what realm of existence we will be reborn into. The second is “completing karma,” which represents all the karma not included in the above category. It is past karma that determines such things as whether one will break a leg or cut a finger. This is completing karma.
The third link is consciousness. Dharma Analysis Treasury says: “Consciousness is the one of the five aggregates that is crucial in the forming of life.” The five aggregates are already present when the child is in the mother’s body. The five aggregates are form, perception, conception, volition, and consciousness. They are also known as the five components.
The fourth link is name and form. Dharma Analysis Treasury says: “What precedes the six sense fields is name and form.”
The fifth link is the six sense fields. Dharma Analysis Treasury says: “After the eyes and other organs are produced, but before the three elements of perception,1 the six sense fields come into being.” The six sense fields are the activities, or output, of the six sense organs, the eyes, ears, nose, tongue, body, and mind.
The sixth link is contact. Dharma Analysis Treasury says: “In the process of perception, the stage before there is any awareness of whether the perception is pleasing, unpleasing, or neutral, is known as contact.” This is the stage in which one does not yet understand that fire is hot, that water is cold, or that a knife is something that can cut a person.
The seventh link is sensation, or perception. Dharma Analysis Treasury says: “The stage before any inordinate desire exists is called sensation.” At this time one understands that a thing is hot or cold, but has not yet experienced any sexual desire.
The eighth link is desire. Dharma Analysis Treasury states: “The craving for material goods or sexual satisfaction is called desire.” This refers to the time when one desires a woman and has feelings of sexual desire.
The ninth link is attachment. Dharma Analysis Treasury says: “Because one hopes to acquire various objects, one races here and there in search of them, and this is called attachment.” This means that while one is in this present life, one pursues worldly affairs and is greedy tograsp and acquire things that belong to others.
The tenth link is existence. Dharma Analysis Treasury states: “Existence means that one performs karmic actions that will determine the kind of fruit, or state of existence, that one will have at one’s next birth.” That is, existence here refers to the carrying out of karmic actions that will lead to one’s receiving life once more in a future existence.
The eleventh link is birth. Dharma Analysis Treasury says: “Birth refers to the receiving of life in one’s next existence.” This refers to the time when one receives life in a future existence and enters the womb of one’s mother.
The twelfth link is aging and death. Dharma Analysis Treasury says: “Until one reaches the stage of sensation in one’s future existence, one is subject to aging and death.” To be subject to birth, aging, and death means that one suffers the anxieties and distress of aging and death.
Question: How do the twelve links in the chain of causation apply tothe three realms of past, present, and future and the two categories of cause and effect?
Answer: Ignorance and action represent two causes in a being’s past existence. Consciousness, name and form, the six sense organs, contact, and sensation represent five effects that appear in a being’s present existence. Desire, attachment, and existence represent three causes appearing in a being’s present existence. Birth and aging and death represent two effects that will appear in a being’s future existence.
I will summarize these as follows: two causes in the past (ignorance, action), five effects in the present (consciousness, name and form, the six sense organs, contact, sensation), three causes in the present (desire, attachment, existence), and two effects in the future (birth, aging and death).
Question: How does the twelve-linked chain of causation operate when it applies to the process of transmigration?
Answer: Ignorance is the condition that causes or brings about action, action brings about consciousness, consciousness brings about name and form, name and form bring about the six sense organs, the six sense organs bring about contact, contact brings about sensation, sensation brings about desire, desire brings about attachment, attachment brings about existence, existence brings about birth, and birth brings about the anxieties and distress of aging and death.
Thus it is that one transmigrates through the sea of the sufferings of birth and death. This is how one comes to be an ordinary mortal.
Question: How does one go about wiping out the twelve-linked chain of causation, thereby attaining emancipation?
Answer: Wipe out ignorance and action will be wiped out. Wipe out action and consciousness will be wiped out. Wipe out consciousness and name and form will be wiped out. Wipe out name and form and the six sense organs will be wiped out. Wipe out the six sense organs and contact will be wiped out. Wipe out contact and sensation will be wiped out. Wipe out sensation and desire will be wiped out. Wipe out desire and attachment will be wiped out. Wipe out attachment and existence will be wiped out. Wipe out existence and birth will be wiped out. Wipe out birth and this will wipe out the anxieties and distress of aging and death. This is how one wipes out the chain of causation, thereby attaining emancipation. This is how the Buddha frees himself from earthly desires.
In my view, persons who are in the intermediate state between death and a new life are not affected by all of the links in the twelve-linked chain of causation. Likewise, beings in the heavenly realm are not affected by all of them. And likewise, beings in the world of formlessness are not affected by all of them."


text:
How is enlightenment or mindfulness reflected in the functioning of the aggregates?
How are the aggregates affected by a person's becoming enlightened or more enlightened?
I'm guessing that some aggregates (e.g. "form" perhaps) are not affected, and some are.
I'm asking, hoping to better understand what an enlightened state of mind is, or in what way it functions differently.
How does "mindfulness" affect the aggregates, what's the change (in the functioning of each aggregate) depending on whether or not you're being mindful?
Is this a wrong question -- were/are the "aggregates" only taught in the context of their being something inconstant and not worth attaching to?

It is not a ‘wrong kind of Question’, but you are asking it from a ‘wrong kind of people’. A person who has some understanding of the proper Maghadi words and their true meaning will give one kind of answer, and those who tend to read English versions of Buddha Dhamma manufactured by lay people will give another answer, and that’s the answer that is going to come a winner. – it is just a thought (IMHO)

Is there any such gradation like 'enlightened' or 'more enlightened' ?

Five aggregates arise in an Arahanth too while living except for the moment of attaining Nibbana and when in Nirodha Samapatti. But the difference is craving, aversion, ignorance are missing, which would otherwise include in the Sankhara aggregate. Also, unpleasant mental feelings(vedana) are missing in the Vedana aggregate. Any Rupa that usually arises due to anger, craving are also not arising. Ex: body temperature rising due to anger.

How are the aggregates affected by a person's becoming enlightened or more enlightened?
As far as I understand , for an enlightened mind the aggregates will cease to exist because the mind will no longer cling to the aggregates. Because with the cessation of clinging, cessation of existence … cessation of birth … aging-and-death, sorrow, lamentation, pain, displeasure, and despair cease. The cessation of this whole mass of suffering will happen. This includes cessation of forms, feelings,perceptions, consciousness and volitional formations.
How does "mindfulness" affect the aggregates, what's the change (in the functioning of each aggregate) depending on whether or not you're being mindful?
To be mindfully aware of not clinging to the aggregates(as long as they are present) is mindfulness. Logically for a mindful person aggregates will cease to exist once enlightenment is achieved.
Is this a wrong question -- were/are the "aggregates" only taught in the context of their being something inconstant and not worth attaching to?
Aggregates are taught with reference to getting rid of the idea of self which is present in most of us. Conceiving self is like a disease and a person conceives self through the aggregates. Aggregates are taught in this context.
I have tried to answer logically based on whatever I have learned till now. Hope this helps.

cool, this matches my answer!

In my understanding of their meaning, the "five heaps of wood" also known as The Five Aggregates, is a schema explaining phenomenological makeup of our subjective existence. In other words, everything that we can ever be aware of, is like a soup made from the following types of ingredients:

Raw stimuli (rupa)
Feelings (vedana)
Notions (samjna)
Memories (samskara)
Interpreted Experiences (vijnana)

This may not be very precise from modern cognitive science perspective, but that's not the point. The point is to show how our entire world with its seemingly infinite complexity and troubles can be simplified to only a few ingredients. When one sees the world in terms of these ingredients, it seems almost comical to take the usual drama seriously. This is the true meaning of Satipatthana practice, to switch one's attention to a different descriptive framework, in order to enable emotional detachment and gain control over one's mind.
The way our subjective existence develops from scratch is explained in the teaching on Twelve Chainlinks, or nidanas:

Initial Non-differentiation (avijja)
Naive Imprinting or Accumulation of Memories (samskara)
Naive Interpretation (vijnana)
Naive Identification (namarupa) and Conceptualization (samjna)
Naive experience of ourselves as a "house with six doors" (salayatana)
Naive experience of "contact" with "external object" (phassa)
Naive association of internal feeling as something coming from the contact with an external object (vedana)
Craving for that experience (tanha)
Obsessing and pursuing of that experience (upadana)
Conflict with the world and resulting individuation (bhava)
Self-identification with the living organism (jati)
All kinds of trouble (jaramarana)

Again, I'm not sure I got all the details 100% right, but the main point is that subjective experience develops from complete non-differentiation -- to a full-blown individuation, through a series of steps that build on one another. Generally speaking, we learn to recognize and differentiate our experiences, until we develop attachments to some of them, and from this attachment comes a sense of conflict with the world which eventually arises as a notion of separate "I". Also note how four of these refer corresponding skandhas.
Because this process is entirely pre-conscious, we're only aware of its result - the experience of being a sentient being living in the world. We are not aware of the mechanisms at play, because we (=our experience of ourselves) are a result of this process! However, this process comes with a payload of trouble, due to the tendency of reification and conflict built into it's very foundation.
Enlightenment involves gradual liberation from the limitations of experience imposed by this process. This liberation is done through detachment from "realities" generated by the process (so called "self" and "world"), through increased awareness of the process' mechanisms and their implications, and through learning a new, higher, mode of perception that does not involve naive reification of our interpretations as the reality. As this Enlightenment progresses, we start seeing through the magic tricks of the process. In this sense we can say that the twelve steps of individuation are getting undone:

"Now from the remainderless fading & cessation of that very Ignorance comes the cessation of [Naive Imprinting]. From the cessation of [Naive Imprinting] comes the cessation of [Naive Interpretation]. From the cessation of [Naive Interpretation] comes the cessation of [Naive Identification and Conceptualization]. From the cessation of [Naive Identification and Conceptualization] comes the cessation of [Us-As-House-With-Six-Doors]. From the cessation of [Us-As-House-With-Six-Doors] comes the cessation of [Naive Experience of Contact]. From the cessation of [Naive Experience of Contact] comes the cessation of [Naive Attribution of Feeling]. From the cessation of [Naive Attribution of Feeling] comes the cessation of [Craving]. From the cessation of [Craving] comes the cessation of [Obsession/Pursuing]. From the cessation of [Obsession/Pursuing] comes the cessation of [Individuation]. From the cessation of [Individuation] comes the cessation of [Self-Identification-With-A-Living-Organism]. From the cessation of [Self-Identification-With-A-Living-Organism], then aging & death, sorrow, lamentation, pain, distress, & despair all cease. Such is the cessation of this entire [burning] heap of stress & suffering."

According to my teacher, the reason we learn Five Skandhas and the phenomenological mode, is to detach from the original "view" of the world, to stop assuming that our interpretation is reality. In order to facilitate this detachment we learn a different "view" (also known as "the raft") - the view of Five Skandhas etc. As we practice Satipatthana and get in the habit of maintaining this phenomenological view, we detach from the original naive view of the world and learn to control our mind. But this second view is not the ultimate reality either! It is only a provisional tool, designed to help us overcome our naive attachment to the first view. Once we develop enough insight, we realize that all views are just that, views, or interpretations - and none of them can be called primary. This liberation from all views, in practice, not just conceptually, leads to emergence of a new way of perception/cognition that in some sense can be called "multidimensional" or "transconceptual".
This transcendental perception is immune to reification, immune to attachment, and therefore immune to any sense of conflict and suffering.
Finally, to answer your question: with achievement of that transcendental perception, "the raft" is no longer necessary, so the Five Aggregates model is no longer relevant or applicable. We could certainly come back and say that Raw Stimuli remain more or less the same, that Feelings are no longer attributed to an external object, that Notions lose their solidity, that Memory Imprints are purified, and that Interpreted Experience is transcended - but this would be dragging ourselves back into confines of a view. So in this sense, Five Aggregates disappear, or are recognized as "empty":

Bodhisattva Avalokiteshvara, performing meditation in the deep Prajna-Paramita realized thus:
  There are Five Heaps, and they by their nature are empty.
  Hey Shariputra, rupa is emptiness, and emptiness if rupa. Emptiness is not different from rupa, and rupa is not different from emptiness. What is rupa is emptiness, what is emptiness is rupa. The same is true of Vedana, Samjna, Samsara, and Vijnana.
Shariputra, all phenomena have the character of emptiness.
  They have no beginning and no end.
  They are not pure, neither are they impure.
  They do not decrease, neither do they increase.
Therefore, in emptiness, there is no Rupa, no Vedana, no Samjna, no Vijnana
  ...

This is why Buddha's subjective experience is called "indescribable" - because it actually transcends any single view.
Now, on intermediate stages of development, we may either catch a practitioner at a phase when he or she is squarely focused on seeing everything in terms of The Five Skandhas... or the next phase, when he or she is beginning to see the approximating/conventional nature of concepts... or the next phase, when he or she is beginning to lose solidity of any single view.
(I realize the above is far from being an obvious interpretation of Buddhism. However, this is what I've got from my decades of study and practice, under several different traditions, with live teachers, reading books, and meditating. So far, this is the only interpretative framework that fits with all sources and all traditions of Buddhism I have ever encountered. I don't claim omniscience, but I claim that I did my homework. You're free to ignore this, or you can try this on as a dress and see if it fits.)

This is quite self-explanatory from Itivuttaka 44 below on the relationship between enlightenment and the five aggregates:

This was said by the Blessed One, said by the Arahant, so I have
  heard: "Monks, there are these two forms of the Unbinding property.
  Which two? The Unbinding property with fuel remaining, & the Unbinding
  property with no fuel remaining.
And what is the Unbinding property with fuel remaining? There is the
  case where a monk is an arahant whose fermentations have ended, who
  has reached fulfillment, finished the task, laid down the burden,
  attained the true goal, ended the fetter of becoming, and is released
  through right gnosis. His five sense faculties still remain and, owing
  to their being intact, he is cognizant of the agreeable & the
  disagreeable, and is sensitive to pleasure & pain. His ending of
  passion, aversion, & delusion is termed the Unbinding property with
  fuel remaining.
And what is the Unbinding property with no fuel remaining? There is
  the case where a monk is an arahant whose fermentations have ended,
  who has reached fulfillment, finished the task, laid down the burden,
  attained the true goal, ended the fetter of becoming, and is released
  through right gnosis. For him, all that is sensed, being unrelished,
  will grow cold right here. This is termed the Unbinding property with
  no fuel remaining."
Commentary (Thanissaro):
  With fuel remaining (sa-upadisesa) and with no fuel remaining
  (anupadisesa): The analogy here is to a fire. In the first case, the
  flames are out, but the embers are still glowing. In the second, the
  fire is so thoroughly out that the embers have grown cold. The "fuel"
  here is the five aggregates. While the arahant is
  still alive, he/she still experiences the five aggregates, but they do
  not burn with the fires of passion, aversion, or delusion. When the
  arahant passes away, there is no longer any experience of aggregates
  here or anywhere else.

This is a very interesting question and one I've been pondering as well! What follows is speculative and more based on reasoning than any specific teaching so please take with a big heap of salt... otoh I can't see how it obviously contradicts what is taught in my tradition?
First, I want to make a distinction between karma and the ordinary mechanics of the world. I don't think it can be said that karma drives the process of a maple seed turning into a maple tree. Why? Because karma is created by intention and action and maple trees are not sentient beings. And yet they age and are subject to causes and conditions. In a similar fashion, I think it is important to separate out the notion of karma from ordinary cause and effect or the mechanics of the world.
Now, one interesting thing to observe is that when a being is enlightened or achieves liberation in this very life the aggregates continue. It is not like upon achieving enlightenment that the body winks out of existence any more than the mind winks out of existence. Not only would that violate the conservation of energy ... it simply isn't the way we observe things to be. It would violate what is known to the world.
Indeed, even after an enlightened or liberated being dies in this very life their corpse remains. Not only does it remain, but with the break up of the body the atoms that were formerly a part of the body of an enlightened being continue. Conservation of energy and matter is observed.
The question could be reformulated maybe as what drives the aging of an enlightened beings body and mind after achieving enlightenment, but before death? For me, I find it inadequate to say that an enlightened beings aging and sickness are caused by past karma for various reasons. Rather, I think that karma must be extinguished upon the pacification of all afflictions. An enlightened or liberated being is no longer subject to suffering and thus past non-virtuous karma that is the cause of suffering must have been extinguished and laid down.
In exactly the same way that an enlightened or liberated beings corpse does not wink out of existence the moment they die I think neither does the mind.
Anyway, I post this not so much as an answer that others should rely upon because undoubtedly I'm very confused or made some egregious error. Rather, I'm hoping someone can help me learn something :)