1 "Kamma is intention (cetanā)."
2 "An arhat generates no new kamma."
Correct, but it needs explanation: while the arhat is still alive (in Samsara), he generates kamma, but only wholesome or neutral kamma. No unwholesome kamma is generated by the arahat. Still, he must bear the bad fruits of extinguishing of his kamma (diseases, aging, bad events, death), but free from suffering. Once the arahat dies, all his remaining kamma gets extinguished, thus he enters Nibanna. In essence, because he does not generate unwholesome kamma and he does not suffer from his unwholesome kamma extinguishing, it can be said that he generates no kamma, because only unwholesome kamma gives fuel to future rebirths.
3 "No new kamma" implies "no rebirth" and is an essential feature of
Correct, but it needs explanation. "No new kamma" implies that a being reached Nirvana and is free from his kamma, thus no rebirth. But it does not mean that before death an enlightened being is not producing new kamma. (read my explanation above about the arahats)
4 "So what is kamma and how can it be ended?"
Kamma is intention.
When intention arises, kamma is accumulated.
When intention ceases, kamma is not accumulated.
Due to the nature of things, kamma is extinguishing.
The nature of things is that all things are impermanent. Thus, the natural process of your kamma is that kamma is naturally extinguishing.
If while your kamma is extinguishing, no intention arises in you, then your kamma will not accumulate and will be extinguished.
Once kamma is extinguished, Nibanna is entered.
5 "An arhat has eliminated identity-view. Kamma is associated with
identity-view ("I am the owner of my actions (kamma), heir to my
actions, born of my actions, related through my actions, and have my
actions as my arbitrator"). An enlightened person acts, but
unselfishly, and so etc. (?)."
6 "Like it is possible to have a "desire to end desire", it's possible
to have an "intention to end kamma". If the only "intention" you
permit yourself is the intention to end karma, then etc. (?)."
Incorrect. Any intention, even if the intention is an intention to end kamma, accumulates kamma.
If you have the "intention to end kamma" it will not end kamma, because the "intention to end kamma" comes from ignorance.
Whoever thinks that with the sole "intention to end kamma", kamma will end, is not free from ignorance and is bound to suffering in the future.
7 "Maybe this answer implies that all cetanā arise, by definition, only
with ignoble mental factors (e.g. ignorance, restlessness, greed,
etc.); so action without ignoble mental factors is (by definition)
without "intention", and is therefore not new kamma (?)."
Incorrect. Any action which is done, ALWAYS arises out of intention, even if all the other mental factors are removed (restlessness, greed, etc.), thus it creates kamma. This is why arahats who are still in their physical bodies (not in Nibanna) still accumulate kamma, but are free from this accumulated kamma. They do not act out of their ignorance, but because they choose to be part of this ignorance (Samsara). They know the truth, they know what is kamma and what is its cessation. Unlike not liberated beings, arahats have a free choice, thus their actions are free from kamma, are not dependent on kamma.
8 "Contradicting this, this answer says that cetanā are responsible for
Right Speech, Right Action, and Right Thought. Do Right Speech and
Right Action create new kamma, if not why not?"
Correct, cetana are responsible for Right Speech, Right Action, and Right Thought. Cetana is responsible for all actions, wholesome, unwholesome or neutral.
Any action creates new kamma.
A liberated being, until he enters Nibanna, creates only wholesome and/or neutral kamma.
9 ""From the cessation of contact is the cessation of kamma" (AN 6.63),
so kamma is ended only when/while there's no contact ... does "no
contact" imply "Jhanas"? But for example sukha (happiness) is
associated with the first jhana, which is a form of contact
(mind-contact)? So anyway, maybe it's something to do with attaining
mastery of the jhanas ... I think someone wrote that the Buddha moved
back into some kind of jhana state between each word he spoke?"
Yes. Kamma is ended only when/while there's no contact.
And when does contact cease completely? In Nibanna.
Going into the deepest Jhana, does not cease contact completely. Think about it ... what if somebody punches you in the face while being in Jhana? What if your body develops a disease while being in Jhana? As you can see, due to your kamma not being completely extinguished, you bear fruits of this kamma, even if being in perfect Jhana. The only way to extinguish your kamma is by ending ignorance and "dying" one last more time, thus entering Nibanna.
10 "This says, "In the Buddha's case, he focused simply on the process of
kammic cause and result as it played itself out in the immediate
present, in the process of developing the skillfulness of the mind,
without reference to who or what lay behind those processes." So apart
from not paying attention to "who", it also focuses on "the immediate
present" -- maybe kamma only happens when you intend/want something to
happen in the future? But I think the Buddha still acted on (present)
cause and (future) effect -- e.g. decide to go somewhere in order to
spend the afternoon there, or to go to Sarnath in order to find the
people to give his first sermon to. I guess that deciding to act
(deciding to go to Sarnath) would cause the stress (e.g. knowledge of
people's need to be taught) to cease, and so the action itself
(actually going to Sarnath) would be relatively stress-free and
without attachment (except perhaps attachment to continuing to do the
right thing) ... but even if that's so, I don't see how to relate that
to "not creating new kamma"."
When I read the passage you quoted, I understood that the Buddha meditated and reached Nirvana:
"On the most basic level of this mode of awareness, there was no sense even of "existence" or "non-existence" [§186], but simply the events of stress, its origination, its cessation, and the path to its cessation, arising and passing away. Through this mode he was able to pursue the fourth type of kamma to its end"
So he went into meditation and gained insight on kamma and realized its workings, thus he ended kamma just like an arahat would end his kamma when reaching Nirvana. (read my explanation above about arahats still generating kamma even after reaching Nirvana).
After reaching Nirvana, the Buddha was still accumulating kamma, but he was free of it completely because his ignorance was removed. He knew kamma, he knew its workings, he knew its cause and its cessation. But out of compassion for other beings he choose to continue generating only wholesome and/or neutral kamma until his kamma completely exhausted due to the real nature of things and entered Nibanna.
11 "It also says, "when there is ignorance of the four noble truths ...
the feeling that results from kamma gives rise to craving ...,
clinging, and becoming; and these, in turn, form the conditions for
further kamma". Is that saying that any Right Intention, which is not
motivated by sensuality, doesn't create new kamma? If so, if this is
the answer, is the difference between sankappa and cetanā significant,
Yes the quote says correctly: when there is ignorance, there is potential for unwholesome kamma to be accumulated, thus giving rise to craving, clinging and becoming, which in turn conditions the accumulation of kamma in the future.
12 "Is that saying that any Right Intention, which is not motivated by
sensuality, doesn't create new kamma?"
Yes, but it needs explanation:
Any Right Intention, which is not motivated by sensuality, DOES create new kamma. But the newly created kamma, because it is not motivated by sensuality, is wholesome and/or neutral kamma, thus the fruits of this kamma will not create suffering, but will aid the owner of this kamma to more easily remove his ignorance and attain Nibanna. Thus, this kamma helps you in extinguishing your kamma.
So correct would be to say: any Right Intention, which is not motivated by sensuality, creates a potential of entering Nibanna, thus ending kamma. So in a way the statement "any Right Intention, which is not motivated by sensuality, doesn't create new kamma" is correct, but it needs to be understood correctly, as I explained.
13 "It also says "because good and bad kamma, consisting of good and bad
intentions, simply perpetuate the ups and downs of experience in the
cosmos, a way must be found out of the mechanism of kamma by mastering
it in a way that allows it to disband in an attentive state of
non-intention". There's a joke in English (actually an American Blues
song) which says, "If it wasn't for bad luck, I wouldn't have no luck
at all". Is Thanissaro Bhikkhu saying "if it weren't for 'good' and
'bad' kamma I would have no kamma at all", i.e. that kamma disappears
when desire and aversion disappear?"
He is saying that the ups and downs produced by kamma actually help you in removing your ignorance and entering Nibanna. Without these ups and downs produced by kamma, you would never need to enter Nibanna because it would be as if you are already in Nibanna (no ups and downs, thus no suffering, thus everything is fine).
This "attentive state of non-intention" is knowledge of the truth. Knowledge of what the truth is, is knowledge about kamma: is knowing kamma, its workings, its cause and its cessation.
14 "The main topic which I misunderstand is what it might mean to "have
no intention" or to "live without intention". It seems to me (using
some ordinary English-language meaning of "intention") that "be or
become enlightened" and "be harmless" and "keep vinaya" and "go on
alms round when hungry" and so on are all examples of "intention" ...
if that's so then how can even an arhat live without intention?"
Becoming enlightened does not mean that intention in you stops. I remember a quote from somewhere that goes like this: "Before enlightenment chop wood and bring water, after enlightenment chop wood and bring water."
Becoming enlightened means that if after enlightenment you decide to stay in Samsara, you will only do wholesome and/or neutral intentions, and always for the greater good of other beings still not liberated.
Becoming enlightened means that you know what intention is, what is its cause and what is the way to its cessation. It does not mean that after enlightenment you stop completely your "intentions", it just means that you know what "intention" is, what is its cause and what its ending.
15 "What the appearance of someone who is "without intention" or "not
generating new kamma": are there visible characteristics, it it
possible to recognize that state when you see it (or conversely to
recognize the absence of that state, to recognize when someone is
generating new kamma)?"
Someone "without intention" or "not generating new kamma" is an arahat or an enlightened being. It is possible to recognize such being by how he behaves in different situations.
16 "Is kamma closely related to fabrications, somehow?"
Because of ignorance fabrications arise.
Fabrications that arose is your kamma.
You respond to these fabrications with different intentions.
With every intention, you fabricate a fabricated thing, which can aid you in reaching Nirvana, deter you from reaching Nirvana or neither aid you nor deter you. In this way you are accumulating fabricated fabrications, which is in essence your kamma.
While fabricating fabrications, due to suffering, you learn what is "good fabrication" and what is "wrong fabrication". You basically learn what is a "wholesome action" and what is an "unwholesome action".
You're learning. Adding, subtracting or modifying your fabricated fabrications depending on already fabricated fabrications. This is you doing actions based on your accumulated kamma.
Until one day you learn enough and realize the truth. You stop fabricating fabrications. You know the end of kamma and enter Nibanna.