Zom wrote:The picture is: young prince Siddhattha spontaneously entered 1st jhana sitting under the tree.
That was quite vivid experience that he remembered (however, it seems, he didn't get any jhana practice knowledge at this moment!).
That's something of an unconjecturable, though his ability to assess the formless attainments ('This Dhamma leads not to disenchantment, to dispassion, to cessation...') tells me he maybe learned something after all. In any event, all he's ultimately going to need to do with this is recollect the factors of the experience as he later assesses various routes to awakening.
Later on he went to Alara & Uddaka. They tought him how to develop these jhanas, so even to reach 4th arupa-sphere.
This begs the question: the texts say those teachers taught certain formless attainments, but they do not mention the four jhanas at all.
He mastered that quickly. However, he was not satisfied with this goal of spiritual life, because he saw that these attainments still lead to rebirth and are not permanent. What is more, it seems, he was not satisfied with the path too, because of the jhanic bliss that he feared (feared probably because the mainstream samana idea of that time was the "harsh asceticism", but not "pleasure asceticism").
Yes, they only lead to a concomitant reappearance. In MN 36 the Bodhisatta recognizes that one must be withdrawn from sensuality in both body & mind, and this is what sets him on his ascetic journeys.
So he searches for a hint, as you say, but he's familiar with his jhanic experience and - as the other samanas would have agreed - such pleasure was off-target. But now it's been years doing formless meditations and then years of ascetic practices, and he wonders about other routes to awakening, and recalls rose-apple jhana.
It's now that he recognizes that there was a pleasure that wasn't connected with sensuality but which was based on seclusion from sensuality: this insight took years to form up, including the realization that physical and
mental seclusion from sensuality was necessary & the recollection that jhana, while pleasurable, fit the bill - quite to the contrary of samana assumptions at this time. (This pleasure, we know, is precisely not to be feared, but to be cultivated.)
Anyway, he recollects the rose-apple experience, not
any training in formless attainments.
That his first two teachers were first in his mind to instruct can be read a number of ways; that they would easily have understood doesn't mean anything about jhana, only about their ability to grasp sammaditthi as stream-enterers, which doesn't require jhana at all.
AN 10.29 wrote:
(9) “Bhikkhus, there are some ascetics and brahmins who proclaim supreme purification. Of those who proclaim supreme purification, this is the foremost, namely, by completely surmounting the base of nothingness, one enters and dwells in the base of neither-perception-nor-non-perception. They teach their Dhamma for the direct knowledge and realization of this. There are beings who assert thus. But even for those who assert thus, there is alteration; there is change. Seeing this thus, the instructed noble disciple becomes disenchanted with it; being disenchanted, he becomes dispassionate toward the foremost, not to speak of what is inferior.
(10) “Bhikkhus, there are some ascetics and brahmins who proclaim supreme nibbāna in this very life. Of those who proclaim supreme nibbāna in this very life, this is the foremost, namely, emancipation through non-clinging after one has seen as they really are the origin and passing away, the gratification, danger, and escape in regard to the six bases for contact.
That sutta reads like a list of outsider practices; and the formless attainment is explicitly said to be so.
Jhanas aren't mentioned at all...?
So jhana is a state with rupa, but this rupa might just be those dhammas of dhamma-mano-vinnana, and in this sense would easily count as a colloquially 'formless' state.
Getting into first jhana while enduring certain sounds (or pain, & probably any intense sensual input) is thorny. Many are the stories of falling away from attaining jhana due to pain, for those who had not yet attained nibbana.
In this, while no sound-ear-vinnana would occur, since the ear & other senses have recourse to the mind, the dhammas there might have certain mental sound components, which I think muddies the phenomenological waters.