The whole rebirth topic has never been a part of my practice. I don't think I've ever even spoken to my teacher about it. Maybe once, and he just waved his hand and said "that's just Indian stuff".
My practice is much more about right action and living wholeheartedly, than contemplating eternal souls and rebirth. Everyone is different, though.
Moreover, if attachment brings suffering, but there is no rebirth, then the insistence on continuing to live is the ultimate attachment. I actually think that this is one possible solution to the Fermi Paradox and supports a pseudo-Buddhist view: eventually civilizations might transcend the biological impulses that keep them attached to life, and then deliberately choose extinction.
For some; it is clearly the most compassionate action even assist with suicide.
We tend to lean towards compassion.
You say “my practice does this” and “my practice does that” and you are certainly entitled to follow whatever religious approach you want. However, I think it would be more honest to label the collection of practices you very deliberately chose as something you could be comfortable with from a contemporary skeptical perspective, as something different from Buddhism.
If that doesn't make me a buddhist, I'm not sure what would :}
Zen is certainly a 'back to basics' movement; but you're quite incorrect so think that zen is separate from historical traditions of buddhism. The buddha sat Shikantaza just as we, all the 'fluff' came later. We are perhaps a 'back to basics' movement, but one that has a several thousand year lineage. Unless you feel Bodhidharma was a dubious modernist? :}
I say 'my practice' as I do not wish to speak for others even inside my group, let alone buddhists as whole.
Believing certain stuff is “fluff” is precisely the dubious attempt at reconstruction that I was talking about.
In terms of their own practices, the Japanese practicing Zen in their own country, and the teachers who came to the West, had the excuse of being born into an existing cultural tradition that had evolved the way it had. First-generation Westerners taking on Buddhism, but only such things as they can feel comfortable with, and then claiming that what they put together is the authentic core Buddhism, just look like cultural appropriators.
Do you think the Indians accused the Chinese of cultural appropriation in the 5th century also?
Even more bizarre to think that chan buddhism (which later became zen) dropped a bunch of stuff they weren't comfortable with when buddhism arrived in china.
Is there some cut off date you think is the high water mark for authentic buddhism? Anything after 1260 need a new name? Buddhism-3? :}
Rebirth being untrue does not imply nothing comes after death. Even Buddha knew that he did not know what came after death. His teachings were about how to live, not about how to win at death.
> But Buddhism has always proscribed suicide ...
Not true. Himsa is proscribed, because it causes harm, and self-harm is still technically himsa, so a simplistic reduction might interpret suicide as proscribed. But such a reduction would also ignore all nuance.
Suicide causes harm. Not just to you, but to your loved ones, and possibly even strangers. Even if we restrict ourselves to an entirely aelfish point of view — where we ignore any auffering we may cause to others — unless you know, for a fact, that there is nothing after death, you cannot believe that you will not have suffering after death.
Yes, the best way Vedantists as well as Buddhists scholars explain this is that even if there is no rebirth, you need to understand that a lot of us agonize ourselves in this life over our own deaths. I have seed devout christians who lived good life just feeling terrified about hell when the moment of death comes near.
The Buddhist and also Hindu doctrine while does address life after death also provides you very actionable advice to avoid suffering in this life itself before death too.
Buddha started with the question: what is the cause of suffering? Desire. But desire is nigh unavoidable in life. Every member of society is likely to have many desires. Thus, everyone is likely to have pain, sooner or later. A person with pain is likely to propagate pain to another person, or more. This a major method through which suffering in society as a whole tends to grow. So we need a way to tell members of society to reduce the propagation of harm. Thus, ahimsa, i.e., do no harm.
But people aren't just gonna internalise such 'for the greater good' ideas, and especially not when they are in pain. Buddha recognised that people often need a strong faith system to root them to these ideas, instead of relying on pure rationality to prevail all the time.
Buddha accepts that we do not really know how the universe works, but this fact does not remove the need for a strong faith system, because humans are imperfect. So — and being a philosopher — Buddha says humans can believe in whatever faith system works for them, as long as the system they choose upholds the core precepts.
The cycle of rebirth and karma just happened to be the predominant faith system at his time, and it also happened to fit the requirements, so most of his followers — at the time — had an easy job of adapting.
But he also warned against believing such faith systems to be the truth, instructing that people must not blindly take his teachings as authority, and must instead examine everything through their own experience and reason through it. When questioned, what to do if such examination reveals a truth that goes against his teachings, he clarified that one must go with the truth. The authority of scripture was explicitly placed below that of one's own experience and reason.
Thus, until proven, the cycle of karma and rebirth is not necessarily true, not is it required to explain that life is suffering and himsa (harm unto) propagates suffering. It's just a convenient way to tie it all together, just as good as any other unproven faith system.
If you don't believe me that Buddhism works just as well without karma and rebirth, take a look at Zen Buddhism. Despite being a modern form of Buddhism, it still holds closely to core of ancient Buddhism. And Zen makes no claim for, or against, the concept of Rebirth. It basically goes, "Idk. Does it matter?". According to Zen, who you are in this life, ceases to exist when you die, and that is plainly observable, so why not live the best life while you have it?
As you can see, this faith system also works to uphold the core precepts of Buddha. And I don't think he'd disagree with Zen on this matter. In fact, he'd probably be glad that Zen has made awakening accessible to people who had no background in the Hindu ideas of karma and rebirth, and thus would have found it harder to reach a path to awakening if they had to adopt those ideas first.