Lang wrote, “In the example of seeing the tree, I used to think of the tree as a vanna rupa.”
You are not alone in that, Lang. Many people have that misconception.
“Instead of a tree, let’s say it is a very attractive, enticing object. If I remember correctly from the Abhidhamma section, then the cakkhudvara citta vithi from seeing that object is followed by 3 manodvara citta vithi. Does the samphassa happen in those three manodvara citta vithi?”
Every time a pancadvara citta vithi runs, three manodvara citta vithi will run following that.
– Samphassa happens in the first pancadvara citta vithi and will also be there in the additional manodvara citta vithi.
“..then for an arahant, are there still 3 (pure) manodvara citta vithi following the cakkhudvara citta vithi, or are there no manodvara citta vithi following it at all?”
Yes. Even for an Arahant, the sequence is the same. But without any samphassa.
– This has to do with the fact that an Arahant will also engage in “neutral activities” like walking, eating, etc. It is just that no abhisankhara will be generated.
Tobias asked: “What rupa are experienced by a gandhabba when he/she is in paraloka or by a deva or a brahma? There is no brain to produce vanna, sadda, rasa, ghanda, pottabba rupa.”
Gandhabba does not need eyes/brain and ears/brain to see and hear. Like for brahmas, they can see and hear at long distances without eyes/ears. See, “Body Types in 31 Realms – Importance of Manomaya Kaya“.
– However, gandhabba can “absorb” scents and can get a bit denser. The word gandhabba comes from “gandha + abba” or “taking in aroma/scents”.
Tobias asked: “As I understand all rupa are made of the 4 great elements. Thus even vanna rupa and also cakkhu rupa are made of these 4 great elements. What determines a cakkhu rupa or what is the “addon” here compared to e.g. a photon?”
– That is the difference between a live being and an inert object. Live beings have hadaya vatthu and a number of pasada rupa (five for humans to zero pasada rupa for the arupavacara brahmas).
– In other words, a living being ALWAYS has a hadaya vatthu to generate thoughts (citta). The only exception is the asanna realm. An asanna being does not generate thoughts, and the fine rupa is maintained by kammic energy.
– This can be easily seen when a human or an animal dies; their mental body with hadaya vatthu gets separated from the dead body, and a dead body is inert just like wood or stone.
– By the way, when the mental body of a yogi comes out of his physical body (say during astral travel), it is still connected to the physical body via kammic energy. That is why that physical body will still have body heat. Of course, at his death, the mental body would be separated and the dead body will get cold.
P.S. In a dead body, there are physical eyes but no mental body with cakkhu pasada rupa.