Oetb asked another question via email:
If the characteristic of that kusala-mula is the desire to attain Nibbana:
Why is only the desire to attain Nibbana for oneself that characteristic, and not too the desire for others to attain Nibbana? (or the desire to help others to attain Nibbana)
Was motivated by the point number 5 of https://puredhamma.net/paticca-samuppada/kusala-mula-paticca-samuppada/
5. With puññābhi saṅkhāra as condition, a puññābhi viññāṇa arises. This puññābhi viññāṇa is accumulated as kamma bhava and could lead to corresponding “good” nāmarupa in pavutti Paṭicca Samuppāda or a new “good birth” in uppatti Paṭicca Samuppāda.
Because the saṅkhāra was generated with a kusala-mula deed, only a kusala-mula viññāṇa arises: “pati +ichcha sama uppada“. The characteristic of this kusala-mula viññāṇa is the desire (chanda, not kāmachanda) for Nibbāna.
I think maybe when I read “desire for Nibbana” I implicitly add “for oneself” as “desire for Nibbana [for oneself]”.
That statement marked in bold also makes me wonder what kind of paticca samuppada cycles for beings not seeking for Nibbana, but doing good deeds and grasping deva or Brahma bhava. Good deeds do not fit in the akusala-mula paticca samuppada, but not seeking Nibbana does not fit in kusala-mula paticca samuppada.
Following was my answer:
You asked: “That statement marked in bold also makes me wonder what kind of paticca samuppada cycles for beings not seeking for Nibbana, but doing good deeds and grasping deva or Brahma bhava.”
For such a person it is the akusala-mula paticca samuppada cycle that comes into play. But the word “akusala” there is at different levels. The worst is when one does dasa akusala (like killing, stealing, etc). That will lead to births in the apayas.
– When one does “good deeds” WITHOUT comprehension of Tilakkhana (anicca, dukkha, anatta) that is also a type of “mild akusala” because one does not realize that even births in the “good realms” will not lead to permanent removal of suffering since, after that good birth, one could still be born in the apayas in the long-run.
That is explained in: “Kusala and Akusala Kamma, Puñña and Pāpa Kamma”
Basically those “good deeds” are done with punna kamma. They are good but not as good as kusala kamma. And, punna kamma automatically becomes kusala kamma after one comprehends Tilakkhana. It is a matter of having a better comprehension of the true nature of this world.
It may take some effort to understand this point. But that is the difference between the “mundane eightfold path” and the “Noble Eightfold Path.”
Also see, “Transition to Noble Eightfold Path”