Coming back to Polak’s analysis of the Sandha Sutta (AN 11.9 - {AN 11.10 in his book}). He rightly points out that 2 types of meditation are contrasted, one to be pursued, and the other not to be pursued. This is preceded by the simile of the 2 types of horses.
Firstly, he is wrong to say that this sutta is concerned with jhana. Jhana is not mentioned at all in the sutta, and it would in fact be very suspicious that the term jhana were applied to the formless attainment in an early strata of the texts. What is used is the verb jhāyati , which simply means “meditates”.
As the simile of the horse shows, the wrong type of meditation is accompanied by the 5 Hindrances, ie craving, while the right type is free of the Hindrances. This then leads to the part that Polak relies upon -
He is absorbed dependent neither on earth, liquid, fire, wind, the sphere of …
per Ven Thanissaro
This is not quite correct. There is no “absorbed” there, or as Polak reads “literally attain jhana”. What it says is in the section on wrong meditation is -
So pathavimpi nissāya jhāyati, āpampi nissāya jhāyati,…
It simply reads - " he meditates dependant on earth etc etc". As mentioned earlier, if this passage is describing the meditator having attained a jhana, that does not fit in with the EBT paradigm of not describing the formless attainments as jhanas.
The presence of nissāya in the wrong meditation leads Polak to then surmise that in a right jhana, there is no relying on meditation objects eg earth, water etc.
If Polak had carried out a larger survey of how nissāya is used, he might have observed the following -
MN 22 - taking the nissāya of a view that does not cause Suffering is impossible
AN 4.159 - the nissāyas being food, craving, clinging and sexual intercourse which lead to rebecoming
Snp 4.9 - where in the context of Magandiya’s search for rebirth, the Buddha asserts the negation of nissāya to end bhava.
It now becomes obvious why AN 11.9 is not describing the jhanas, but describing the attempts at meditating with craving for particular forms of rebirth based on the various attainments. The right meditation is anissāya, not in the sense that one does not rely on meditation objects, but in the sense that one does not rely on craving. That much is clear from the mention of the Hindrances; those are the nissāyas of wrong meditation.
That would explain the devas’ bewilderment, as they cannot imagine a situation where craving is not a nissāya upon which the Buddha meditates.