Indeed there are other suttas:
https://www.buddhismuskunde.uni-hamburg ... o/ebms.pdfDN 1 at DN I 37,1 and its parallels DĀ 21 at T I 93b20, T 21 at T I 269c22, a Tibetan discourse parallel in Weller 1934: 58,3 (§191), a discourse quotation in the *Śāriputrābhidharma, T 1548 at T XXVIII 660b24, and a discourse quotation in D 4094 ju 152a4 or Q 5595 tu 175a8. The same versions also attribute the arising of annihilationist views to the immaterial attainments (for Sanskrit fragments corresponding to the section on annihilationism see also Hartmann 1989: 54 and SHT X 4189, Wille 2008: 307).
Within the Pāli suttas we are told that the following is the doctrine of annihilationists, or some of them:
'I would not be, neither would there be what is mine. I will not be, neither will there be what is mine.'
In MN 106 a similar position, similar to the annihilationist, is a means of entry into Nothingness:
Out of all of the speculative views around, the annihilationist doctrine was foremost as it was close to non-clinging:3. Furthermore, a noble disciple reflects: ‘I don’t belong to anyone anywhere! And nothing belongs to me anywhere!’ Practicing in this way and meditating on it often their mind becomes confident in this dimension. Being confident, they either attain the dimension of nothingness now, or are freed by wisdom. When their body breaks up, after death, it’s possible that the consciousness headed that way will be reborn in the dimension of nothingness. This is said to be the third way of practice suitable for attaining the dimension of nothingness.
https://suttacentral.net/an10.29/en/bodhi(8) “Bhikkhus, of the speculative views held by outsiders, this is the foremost, namely: ‘I might not be and it might not be mine; I shall not be, and it will not be mine.’ For it can be expected that one who holds such a view will not be unrepelled by existence and will not be repelled by the cessation of existence. There are beings who hold such a view. But even for beings who hold such a view 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.
We are told that among the meditative absorptions, ākiñcaññāyatana & nevasaññānāsaññāyatana were foremost. This shows that A) the annihilationist doctrine is best of all of the positions outside of the Dhamma and B) The state of ākiñcaññāyatana & nevasaññānāsaññāyatana are the highest attainments outside of nibbāna. This suggests that the 2 are linked, with ākiñcaññāyatana & nevasaññānāsaññāyatana being the peak of accomplishment among annihilationists. We actually see this link explicitly in MN 106:
In turn, of course, this means Āḷāra Kālāma & Uddaka Rāmaputta were teaching a form of annihilationism, and so the Buddha began his career as an annihilationist. He may very well have never stopped being one of sorts, until his awakening. Perhaps he finally understood that it was his aversion to existence that was, in the end, keeping him tethered to it?“Ānanda, take a mendicant who practices like this: ‘It might not be, and it might not be mine. It will not be, and it will not be mine. I am giving up what exists, what has come to be.’ In this way they gain equanimity. They approve, welcome, and keep clinging to that equanimity. Their consciousness relies on that and grasps it. A mendicant with grasping does not become extinguished.”
“But sir, what is that mendicant grasping?”
“The dimension of neither perception nor non-perception.”
https://suttacentral.net/mn106/en/sujatoWhen he said this, Venerable Ānanda said to the Buddha: “Sir, take a mendicant who practices like this: ‘It might not be, and it might not be mine. It will not be, and it will not be mine. I am giving up what exists, what has come to be.’ In this way they gain equanimity. Would that mendicant become extinguished or not?”
“One such mendicant might become extinguished, Ānanda, while another might not.”
“What is the cause, sir, what is the reason for this?”
“Ānanda, take a mendicant who practices like this: ‘It might not be, and it might not be mine. It will not be, and it will not be mine. I am giving up what exists, what has come to be.’ In this way they gain equanimity. They approve, welcome, and keep clinging to that equanimity. Their consciousness relies on that and grasps it. A mendicant with grasping does not become extinguished.”
“But sir, what is that mendicant grasping?”
“The dimension of neither perception nor non-perception.”
“Sir, it seems that mendicant is grasping the best thing to grasp!”
“Indeed, Ānanda. For the best thing to grasp is the dimension of neither perception nor non-perception.
Take a mendicant who practices like this: ‘It might not be, and it might not be mine. It will not be, and it will not be mine. I am giving up what exists, what has come to be.’ In this way they gain equanimity. They don’t approve, welcome, or keep clinging to that equanimity. So their consciousness doesn’t rely on that and grasp it. A mendicant free of grasping becomes extinguished.”
Regarding the likes of Ajita Kesakambali, can we really say he was a materialist when the mahābhūta are more akin to abstract qualities rather than crude matter? Ajita probably meditated. Given his doctrine it is possible he relied upon ākāsānañcāyatana and could go no further, so we see another possible connection there. Perhaps still, we might muse, that the formless attainments were the method of choice for annihilationists whilst the Jhānā were favoured by eternalists? The Buddha then possibly incorporated both, not just because both were useful, but also as a means to show that he had mastered both the eternalist and annihilationist attainments yet knew of something that was higher still.
