On what basis can a person who chooses to forgo enlightenment (arahant status) for any reason (for the supposed benefit of others, for example) be considered a Buddhist? If there is such a basis, can a person who intentionally retains a wrong view (seeing the body as self, for example) also be considered a Buddhist when they won't renounce such a view once corrected? Or a person who intentionally retains wrong action (stealing), saying that such action benefits others? I am mostly referring to the choice some people make to be a "bodhisattva" when they see that choice as intentionally putting off the efforts and strivings necessary to become enlightened because they would rather work "selflessly" for others' benefit. Where is the support for such a choice found within the Buddha's teachings?
It's a dangerous question, because it invites potential arguments between supporters of particular sects, but I will try to answer in good faith anyway.
The goal of Buddhism is attainment of Nirvana. For simplicity, let's characterize Nirvana as "unconditional peace". As per the Noble Truth such unconditional peace is only possible when there is absolutely no craving. Now, what is craving? Craving is an obsessive desire for something other than what is present here and now. The absence of craving then is 100% satisfaction in the here and now. Such satisfaction can only be unconditional if craving is absent regardless of circumstances. In other words, unconditional peace is the absence of craving for the circumstances to be different than they are now.
Achieving this level of absence of craving and thus mastering the unconditional Peace is the culmination of the Noble Eightfold Path. Now, if someone has attained this Peace, would they have an inner reason to stay away from society? If we think logically, the answer must be a firm and resounding "no!". For one, because in the absence of craving there can't be aversion to society. Second, unconditional peace is, by definition, imperturbable. Finally, staying in society creates possibilities for teaching Dharma, which helps reduce global level of suffering†, something a true self-less Buddhist would be happy to facilitate.
So, as it turns out, an already Enlightened mind would absolutely choose to stay in society to keep helping others.
Now, if an Enlightened mind (~"a Buddha") would lead such lifestyle, why wouldn't we, his students, model after our teacher and lead the same lifestyle even now, before we are fully enlightened? Especially if working on our own Enlightenment, it turns out, is not in conflict with "staying behind"! In fact, upon a closer examination, dropping our aversion to society and our craving for a trascendental escape, is exactly the kind of "letting go" that is required for attaining the unconditional peace of no-craving.
So if we can drop our aversion to society, accept everything in its imperfection, and help other sentient beings reduce the level of dukkha, by abandoning craving - turns out we are de-facto living the state of Buddha that we have supposedly forgone! But if we abandon society and work on our own Liberation, it turns out we in fact are acting out of our selfish aversion and selfish craving! So the path of a Bodhisattva is logically consistent with Dharma while the path of an arahant hides a logical contradiction. Or perhaps the path of an arahant may be a valid provisional training, but at the advanced stages if one were to truly abandon craving, the switch over to Mahayana would happen anyway.
And this is roughly the line of reasoning that led to emergence of Mahayana's ideal of Bodhisattva. I may have made some minor mistakes in connecting the chain of ideas, but the overall argument is more or less valid, I think.
I can't speak for edge cases though. There's obviously a possibility that someone would use this logic to cover up their laziness and complacency. They may even have false views regarding the self, and engage in dukkha-creating activities such as stealing. This is not out of question. But this does not negate the core idea of Mahayana, which is based on the valid understanding of The Goal, The Second and Third Noble Truths, and their real-life implications.
†note how this says "global level of suffering" without mentioning any "sentient beings" - although suffering (dukkha) is, of course, a subjective phenomenon.
As for the Right Intent (defined as intent directed away from Three Poisons and toward dispassion) and Right Effort (defined as effort to stop mindstates conducive to dukkha, and cultivate those conducive to Enlightenment & Peace) - I don't think they are in any conflict with the Bodhisattva's vow. You can perfectly practice both while living in society, and the subject of your practice doesn't even have to be limited to yourself. You can perfectly cultivate dispassion and wholesome mindstates in everyone, without artificially separating other people from yourself.
In Theravada, stream-enterers, once-returners & non-returners have eradicated the view the five aggregates are a real self. However, they may have the ridiculous impossible aspiration to save others. While the Pali suttas say it is not possible to save all sentient beings, the Pali suttas also refer to "rebirth by aspiration" (MN 120). While the meaning of MN 120 may not be absolutely clear, it provides some doctrinal support that a Mahayana Bodhisattva can choose their future course.
My question involves someone also resolving on something other than complete destruction of the taints: continued efforts to help others and improve the world. Does such a choice fall under Wrong Intention & Wrong Effort/Striving?
I think that Mahayana doctrine is that there are two or three types of "obscuration" ...
Obscuration of disturbing emotions. The emotions of the five poisons: anger, desire, stupidity, pride and envy
Obscuration of habitual tendencies
Obscuration of conceptual knowledge. The subtle obscuration of holding on to the concepts of subject, object and action.
The final obscuration of dualistic knowledge preventing the full attainment of buddhahood.
... or four types if you add karmic obscurations.
And I think that the first two of the above are what you called "the taints".
Anyway I think that the Theravada doctrine is that the Buddha is or was an arahant but -- more than that -- also able to teach.
So I assume that someone who would aspire to be a bodhisattva isn't doing that "instead of" the destruction of the taints -- i.e. that they're motivated/intending to destroy the taints, and (as well as, not instead of) the karmic and cognitive obscurations.
And -- as outlined in these comments -- that it's not about "forgoing enlightenment".
A problem with labels like “is a buddhist” or “is not a buddhist” is that it can mean different things to different people. All you’re quantifying is how accurately a specific word pertains to the “being” of a Buddhist. If they are mostly Buddhist, then they are mostly Buddhist.
My problem with religion is that people take them too literally. First of all, knowledge and truth is a physical construct, and life is rather irrational if you think about it. Logically, it is illogical, but why would there be no purpose? I think life is an irrational gift, and that we should all respect the garden we’re grown it! Whether or not you are technically a Buddhist is irrelevant :)
Your questions, householder Kilaya Ciriello, seem to be very serious to get a release from doubt, so my person tries to answer them for this purpose:
On what basis can a person who chooses to forgo enlightenment (arahant status) for any reason (for the supposed benefit of others, for example) be considered a Buddhist?
Taken the modern word "Buddhist" as Upasaka, lay follower, one can be considered as such if having gone for refuge to the Tripple Gems:
from the Mahanama Sutta
"Venerable sir, in what way is one a lay follower?"
"Mahanama, inasmuch as one has gone to the Buddha for refuge, has gone to the Dhamma for refuge, has gone to the Sangha for refuge; in that way, Mahanama, one is a lay follower."
It's necessary to note that the refuge does not require the desire to gain Arahathood, but can be for a good wandering on in Samsara, birth, aging, sickness and death, as well. No such needed to "be" a Upasaka.
(Worthy to note that actually less western, modern, those far away from Sangha, ever really having taken refuge, yet subsisting on something they assume as such.)
If there is such a basis, can a person who intentionally retains a wrong view (seeing the body as self, for example) also be considered a Buddhist when they won't renounce such a view once corrected?
There is no such base, but independent, say one has taken refuge, yet holds wrong views but does not "renounce" the refuge, one is still considered as follower as long as one, having taken the Dhamma as refuge, aware of it, not actually renounces in doing on knowingly. By rejecting deliberatly the Dhamma, one can hardly be expected as follower. One who merely sticks in wrong views would be, as an action by the community (spoken here form the monks, which has been given tools for such), suspended, send away, yet still part, still member (just in short mentioned as example)
Or a person who intentionally retains wrong action (stealing), saying that such action benefits others?
The same here like before. One, as a layperson, would simply be recognized as a "unvirtouse" Upasaka. As one who has left home under the tripple Gems, certain actions could lead one to be expelled from the community, even to an amount of no more able to rejoin. Note that householders, following, are not really considered as carrier and so do not underlie certain "justice", considered as being not that harmful for the religion as homeless, monks, could.
I am mostly referring to the choice some people make to be a "bodhisattva" when they see that choice as intentionally putting off the efforts and strivings necessary to become enlightened because they would rather work "selflessly" for others' benefit.
"bodhisattvas", at large, can seldom be considered as refugees, seldom have gone for refuge. Do seldom anything the Buddha adviced, are seldom after such.
Where is the support for such a choice found within the Buddha's teachings?
Bodhisattas, by it's nature, would fall out of their aspiration if having heard the good Dhamma, gained right view, wisdom. There can be no encouragement for such aspirations outside the heritage walking, be found, yet, as told at the beginning, if one is not really aware of ones wrong view, such a person can still be considered as "Buddhist", known as one holding on wrong views, if actually having gone to the Sublime Buddha, his Dhamma, his Sangha, for refuge.
Some further food for thoughts on "Can a Bodhisattva be considered as 'Buddhist'", here, incl space for discussion: Is it possible that a Bodhisttva is a member of the Sangha?
More on what is called a Dhammika (Buddist by heart and deeds): Dhammika Sutta: Dhammika.
It's, how ever, possible good to note, that the Buddha did not expect all his follower to walk the most staight way. One after a good life here, a life dedicated merely to the world, the doing of merits, the increasing od Paramis, perfections... all this does not necessary, rather less, contradict the refuge and what is praised by the wise. So there is in now way something to blame on generosity, help... in harmless ways and in accordiance and following actually the Buddhas advices, of the Dhamma. It's btw. posible the best access to the path n t's whole to go after the aspiration seeking to help all beings an get on the way thing good and better understood, foremost the 1st Noble Truth, suffering and soon it's cause.
Sadhu for your ways, as displayed in your persons introductions, btw. and may they soon lead householder gain paths fruits and highest liberation.
(Note that this is not given for trade, stacks, exchange and entertainments, holding one in this wheel, but as a means for release from it)