“I’d like to know why the paccuppanna rūpakkhanda excepted.”
– Yes. That should not be excluded. It takes a fraction of a second for the “image of a rupa” to go through the mind, and it is instantly registered. I will delete that sentence tomorrow.
“I am still looking for the key criterion to distinguish between nāma and rūpa. Why rūpakkhanda is not nāma? I am asking this question because rūpakkhanda was not mentioned.”
– The mind can “see” rupakkhandha, i.e., it can “see” the shape, features, etc. of a rupa.
– For example, when we see a tree, the mind sees it with its trunk, branches, leaves, etc.
– However, only the “necessary ingredients (vedana, sanna, sankhara, vinnana) that can “re-create” that “image of the tree” is preserved in the namaloka as namagotta. When those ingredients are reflected back to the mind as “dhammā,” the mind can re-create the “image of the tree.” In other words, namagotta are NOT rupakkhandha.
The post, “Difference Between Physical Rūpa and Rūpakkhandha” could help figure it out.