Questions on The Eight kinds of emancipations as described in the suttas

While reading through the Buddhist suttas, I came across the detailed descriptions of the eight emancipations. These passages were deeply intriguing, but they also gave rise to some questions in my mind which I decided to ask before which let me cite the concerned passages - > “Ānanda, there are these eight emancipations. Which eight? > > “**Possessed of form, one sees forms.** This is the first > emancipation. > > “**Not percipient of form internally, one sees forms externally.** > This is the second emancipation. > > “**One is intent only on the beautiful.** This is the third > emancipation. > > “**With the complete transcending of perceptions of (physical) form, > with the disappearance of perceptions of resistance, and not heeding > perceptions of multiplicity, (perceiving,) ‘Infinite space,’ one > enters and remains in the dimension of the infinitude of space**. This > is the fourth emancipation. > > **“With the complete transcending of the dimension of the infinitude of space, (perceiving,) ‘Infinite consciousness,’ one enters and > remains in the dimension of the infinitude of consciousness.** This is > the fifth emancipation. > > **“With the complete transcending of the dimension of the infinitude of consciousness, (perceiving,) ‘There is nothing,’ one enters and > remains in the dimension of nothingness.** This is the sixth > emancipation. > > **“With the complete transcending of the dimension of nothingness, one enters and remains in the dimension of neither perception nor > non-perception.** This is the seventh emancipation. > > **“With the complete transcending of the dimension of neither perception nor non-perception, one enters and remains in the cessation > of perception and feeling.** This is the eighth emancipation. > > “**Now, when a monk attains these eight emancipations in forward > order, in reverse order, in forward and reverse order**, when he > attains them and emerges from them wherever he wants, however he > wants, and for as long as he wants, when through the ending of > effluents he enters and remains in the effluent-free release of > awareness and release of discernment, having directly known it and > realized it for himself in the here and now, **he is said to be a monk > released in both ways. And as for another release in both ways, higher > or more sublime than this, there is none.”** ~ DN 15 Questions- 1. Why is “nothingness” (6th) distinguished from “neither perception nor non-perception” (7th), given that both involve retreating from mental activity? Or from the 8th which involves total cessation of perception and feeling? 2. What kind of experience is “neither perception nor non-perception”? Is it a liminal state — and if so, how does one know they have entered it? Can a mind in this state be said to ‘experience’ anything at all? 3. In discussions with scholars from eternalist backgrounds, such as vedanta a common challenge raised is that the Buddhist teachings on the eight emancipations seem to imply the existence of a continuous or eternal subject since someone appears to be progressing through these subtle states of consciousness. If there is no eternal soul or self in Buddhism, then who is it that experiences and moves through these emancipations? How would a Buddhist respond to this objection? 4. What is the significance of being able to enter and exit these states at will, as emphasized in the sutta? 5. Is the progression through these states ultimately teaching that liberation is not something to be gained, but everything to be let go including perception, feeling, identity, and knowing?