Allness of All

One of the very known suttas in Pali Canon is SN 35.23. Unfortunately very often the sutta is misunderstood. Too many Buddhists tend to think that the sutta means nothing exists beyond six spheres of perception. This is not so.

An excellent comment of Thanissaro Bhikkhu:

The Commentary’s treatment of this discourse is very peculiar. To begin with, it delineates three other “All’s” in addition to the one defined here, one of them supposedly larger in scope than the one defined here: the Allness of the Buddha’s omniscience (literally, All-knowingness). This, despite the fact that the discourse says that the description of such an all lies beyond the range of explanation.
Secondly, the Commentary includes nibbana (unbinding) within the scope of the All described here — as a dhamma, or object of the intellect — even though there are many other discourses in the Canon specifically stating that nibbana lies beyond the range of the six senses and their objects. Sn 5.6, for instance, indicates that a person who has attained nibbana has gone beyond all phenomena (sabbe dhamma), and therefore cannot be described. MN 49 discusses a “consciousness without feature” (viññanam anidassanam) that does not partake of the “Allness of the All.” Furthermore, the following discourse (SN 35.24) says that the “All” is to be abandoned. At no point does the Canon say that nibbana is to be abandoned. Nibbana follows on cessation (nirodha), which is to be realized. Once nibbana is realized, there are no further tasks to be done.
Thus it seems more this discourse’s discussion of “All” is meant to limit the use of the word “all” throughout the Buddha’s teachings to the six sense spheres and their objects. As the following discourse shows, this would also include the consciousness, contact, and feelings connected with the sense spheres and their objects. Nibbana would lie outside of the word, “all.” This would fit in with another point made several times in the Canon: that dispassion is the highest of all dhammas (Iti 90), while the arahant has gone beyond even dispassion (Sn 4.6; Sn 4.10).
This raises the question, if the word “all” does not include nibbana, does that mean that one may infer from the statement, “all phenomena are not-self” that nibbana is self? The answer is no. As AN 4.174 states, to even ask if there is anything remaining or not remaining (or both, or neither) after the cessation of the six sense spheres is to differentiate what is by nature undifferentiated (or to objectify the unobjectified — see the Introduction to MN 18). The range of differentiation goes only as far as the “All.” Perceptions of self or not-self, which would count as differentiation, would not apply beyond the “All.” When the cessation of the “All” is experienced, all differentiation is allayed

Consciousness without feature

Consciousness without feature,
 without end,
luminous all around:
Here water, earth, fire, & wind
have no footing.
Here long & short
coarse & fine
fair & foul
name & form
are all brought to an end.
With the cessation of [the activity of] consciousness
each is here brought to an end.

Where water, earth, fire, & wind have no footing: There the stars don’t shine, the sun isn’t visible. There the moon doesn’t appear. There darkness is not found. And when a sage, a brahman through sagacity, has realized [this] for himself, then from form & formless, from bliss & pain, he is freed.

There is that dimension, monks, where there is neither earth, nor water, nor fire, nor wind; neither dimension of the infinitude of space, nor dimension of the infinitude of consciousness, nor dimension of nothingness, nor dimension of neither perception nor non-perception; neither this world, nor the next world, nor sun, nor moon. And there, I say, there is neither coming, nor going, nor staying; neither passing away nor arising: unestablished, unevolving, without support [mental object]. This, just this, is the end of stress.

“Just as if there were a roofed house or a roofed hall having windows on the north, the south, or the east. When the sun rises, and a ray has entered by way of the window, where does it land?”
“On the western wall, lord.”
“And if there is no western wall, where does it land?”
“On the ground, lord.”
“And if there is no ground, where does it land?”
“On the water, lord.”
“And if there is no water, where does it land?”
“It does not land, lord.”

“In the same way, where there is no passion for the nutriment of physical food … contact … intellectual intention … consciousness, where there is no delight, no craving, then consciousness does not land there or grow. Where consciousness does not land or grow, name-&-form does not alight. Where name-&-form does not alight, there is no growth of fabrications. Where there is no growth of fabrications, there is no production of renewed becoming in the future. Where there is no production of renewed becoming in the future, there is no future birth, aging, & death. That, I tell you, has no sorrow, affliction, or despair.”

Sandcastles

At Sāvatthī.

Seated to one side, Venerable Rādha said to the Buddha:

“Sir, they speak of this thing called a ‘sentient being’. How is a sentient being defined?”

“Rādha, when you cling, strongly cling, to desire, greed, relishing, and craving for form, then a being is spoken of. When you cling, strongly cling, to desire, greed, relishing, and craving for feeling … perception … choices … consciousness, then a being is spoken of.

Suppose some boys or girls were playing with sandcastles. As long as they’re not rid of greed, desire, fondness, thirst, passion, and craving for those sandcastles, they cherish them, fancy them, treasure them, and treat them as their own. But when they are rid of greed, desire, fondness, thirst, passion, and craving for those sandcastles, they scatter, destroy, and demolish them with their hands and feet, making them unplayable.

In the same way, you should scatter, destroy, and demolish form, making it unplayable. And you should practice for the ending of craving. You should scatter, destroy, and demolish feeling … perception … choices … consciousness, making it unplayable. And you should practice for the ending of craving. For the ending of craving is extinguishment.”

https://suttacentral.net/sn23.2/en/sujato

Atman

It is interesting that Atman in ancient India was understood absolutely not like we understand the Soul.

The microcosm (man) mirrors the macrocosm (the universe). Both have an essence, a true nature, a ‘self ’ (atman), which is the same for both. So at the cosmic level brahman and atman are to be understood as synonyms. Being an essence, that atman is unchanging: it is being as opposed to becoming. Being is also a plenum, since it can be predicated of everything that exists. Unhappiness is always due to a lack of something; being, a plenum, can lack nothing; therefore being has no unhappiness, but is bliss. (c) R. Gombrich “How Buddhism Began”

How Buddha practiced meditation himself

On arrival, they saw the Blessed One sitting in the grove — his legs folded crosswise, his body set straight, mindfulness established to the fore. On seeing him, they went to the brahman of the Bharadvaja clan and, on arrival, said to him, “Sir, you should know that Gotama the contemplative is in that grove over there, sitting with his legs folded crosswise, his body set straight, mindfulness established to the fore.”

So the brahman of the Bharadvaja clan, together with the youths, went to the forest grove. On arrival, he saw the Blessed One sitting in the grove — his legs folded crosswise, his body set straight, mindfulness established to the fore. On seeing him, he went to the Blessed One and, on arrival, addressed him in verse:

In the deep-looking forest,
teeming with terrors,
having plunged into the wilderness
— desolate, empty —
unflinchingly, steadfastly, compellingly,
you practice jhana, monk:
How very lovely you look!
https://www.accesstoinsight.org/tipitaka/sn/sn07/sn07.018.than.html

On Abhidharma

Numerous Abhidharma traditions arose in India, roughly during the period from the 2nd or 3rd Century BCE to the 5th Century CE. The 7th-century Chinese pilgrim Xuanzang reportedly collected Abhidharma texts from seven different traditions. The various Abhidhammic traditions have very fundamental philosophical disagreements with each other. These various Abhidhammic theories were (together with differences in Vinaya) the major cause for the majority of splits in the monastic Sangha, which resulted in the fragmented early Buddhist landscape of the 18 Early Buddhist Schools.

In the modern era, only the Abhidharmas of the Sarvāstivādins and the Theravādins have survived intact, each consisting of seven books, with the addition of the Sariputra Abhidharma. The Theravāda Abhidharma, the Abhidhamma Pitaka (discussed below), is preserved in Pāli, while the Sarvāstivādin Abhidharma is mostly preserved only in Chinese – the (likely Sanskrit) original texts having been lost, though some Tibetan texts are still extant. A small number of other Abhidharma texts of unknown origin are preserved in translation in the Chinese canon. These different traditions have some similarities, suggesting either interaction between groups or some common ground antedating the separation of the schools.

Also, the Pali version of the Abhidhamma is a strictly Theravada collection, and has little in common with the Abhidhamma works recognized by other Buddhist schools. The earliest texts of the Pali Canon have no mention of (the texts of) the Abhidhamma Pitaka. The various Abhidhamma philosophies of the various early schools have no agreement on doctrine.

For the Abhidharmikas, the ultimate components of existence, the elementary constituents of experience were called dharmas The “base upon which the entire [Abhidharma] system rests” is the ‘dharma theory’ and this theory ‘penetrated all the early schools’
These dharmas were seen as the ultimate entities or momentary events which make up the fabric of people’s experience of reality.

More on Dhamma theory:

Stopping of the six contact-media

Then Ven. Maha Kotthita went to Ven. Sariputta and, on arrival, exchanged courteous greetings with him. After an exchange of friendly greetings & courtesies, he sat to one side. As he was sitting there, he said to Ven. Sariputta, “With the remainderless stopping & fading of the six contact-media [vision, hearing, smell, taste, touch, & intellection] is it the case that there is anything else?”
[Sariputta:] “Don’t say that, my friend.”
[Maha Kotthita:] “With the remainderless stopping & fading of the six contact-media, is it the case that there is not anything else?”
[Sariputta:] “Don’t say that, my friend.”
[Maha Kotthita:] “…is it the case that there both is & is not anything else?”
[Sariputta:] “Don’t say that, my friend.”
[Maha Kotthita:] “…is it the case that there neither is nor is not anything else?”
[Sariputta:] “Don’t say that, my friend.”
[Maha Kotthita:] “Being asked if, with the remainderless stopping & fading of the six contact-media, there is anything else, you say, ‘Don’t say that, my friend.’ Being asked if … there is not anything else … there both is & is not anything else … there neither is nor is not anything else, you say, ‘Don’t say that, my friend.’ Now, how is the meaning of your words to be understood?”
[Sariputta:] “The statement, ‘With the remainderless stopping & fading of the six contact-media [vision, hearing, smell, taste, touch, & intellection] is it the case that there is anything else?’ objectifies non-objectification. The statement, ‘… is it the case that there is not anything else … is it the case that there both is & is not anything else … is it the case that there neither is nor is not anything else?’ objectifies non-objectification. However far the six contact-media go, that is how far objectification goes. However far objectification goes, that is how far the six contact media go. With the remainderless fading & stopping of the six contact-media, there comes to be the stopping, the allaying of objectification.

“And suppose someone were to ask you, ‘This fire that has gone out in front of you, in which direction from here has it gone? East? West? North? Or south?’ Thus asked, how would you reply?”

“That doesn’t apply, Master Gotama. Any fire burning dependent on a sustenance of grass and timber, being unnourished — from having consumed that sustenance and not being offered any other — is classified simply as ‘out’ (unbound).”

“Even so, Vaccha, any physical form by which one describing the Tathagata would describe him: That the Tathagata has abandoned, its root destroyed, made like a palmyra stump, deprived of the conditions of development, not destined for future arising. Freed from the classification of form, Vaccha, the Tathagata is deep, boundless, hard to fathom, like the sea. ‘Reappears’ doesn’t apply. ‘Does not reappear’ doesn’t apply. ‘Both does & does not reappear’ doesn’t apply. ‘Neither reappears nor does not reappear’ doesn’t apply.

About Nirvana

There is, monks, an unborn — unbecome — unmade — unfabricated. If there were not that unborn — unbecome — unmade — unfabricated, there would not be the case that emancipation from the born — become — made — fabricated would be discerned. But precisely because there is an unborn — unbecome — unmade — unfabricated, emancipation from the born — become — made — fabricated is discerned.

Unanswered questions

“Mālunkyāputta, if there is the view ‘the world is eternal,’ the holy life cannot be lived; and if there is the view ‘the world is not eternal,’ the holy life cannot be lived. Whether there is the view ‘the world is eternal’ or the view ‘the world is not eternal,’ there is birth, there is ageing, there is death, there are sorrow, lamentation, pain, grief, and despair, the destruction of which I prescribe here and now.

“If there is the view ‘the world is finite,’…‘the world is infinite, ’…‘the soul is the same as the body,’…‘the soul is one thing and the body another,’…‘after death a Tathāgata exists,’…‘after death a Tathāgata does not exist,’ the holy life cannot be lived… If there is the view ‘after death a Tathāgata both exists and does not exist,’ the holy life cannot be lived; and if there is the view ‘after death a Tathāgata neither exists nor does not exist,’ the holy life cannot be lived. Whether there is the view ‘after death a Tathāgata both exists and does not exist’ or the view ‘after death a Tathāgata neither exists nor does not exist,’ there is birth, there is ageing, there is death, there are sorrow, lamentation, pain, grief, and despair, the destruction of which I prescribe here and now.

“Therefore, Mālunkyāputta, remember what I have left undeclared as undeclared, and remember what I have declared as declared. And what have I left undeclared? ‘The world is eternal’—I have left undeclared. ‘The world is not eternal’—I have left undeclared. ‘The world is finite’—I have left undeclared. ‘The world is infinite’—I have left undeclared. ‘The soul is the same as the body’—I have left undeclared. ‘The soul is one thing and the body another’—I have left undeclared. ‘After death a Tathāgata exists’—I have left undeclared. ‘After death a Tathāgata does not exist’—I have left undeclared. ‘After death a Tathāgata both exists and does not exist’—I have left undeclared. ‘After death a Tathāgata neither exists nor does not exist’—I have left undeclared.

“Why have I left that undeclared? Because it is unbeneficial, it does not belong to the fundamentals of the holy life, it does not lead to disenchantment, to dispassion, to cessation, to peace, to direct knowledge, to enlightenment, to Nibbāna. That is why I have left it undeclared.

https://suttacentral.net/mn63/en/bodhi