I’m not entirely sure what you are asking, but maybe this excerpt from Ven. Bhikkhu Bodhi’s essay on sankhara is helpful:
“ The third major domain in which the word sankhara occurs is as a designation for all conditioned things. In this context the word has a passive derivation, denoting whatever is formed by a combination of conditions; whatever is conditioned, constructed, or compounded. In this sense it might be rendered simply “formations,” without the qualifying adjective. As bare formations, sankharas include all five aggregates, not just the fourth. The term also includes external objects and situations such as mountains, fields, and forests; towns and cities; food and drink; jewelry, cars, and computers.
The fact that sankharas can include both active forces and the things produced by them is highly significant and secures for the term its role as the cornerstone of the Buddha’s philosophical vision. For what the Buddha emphasizes is that the sankharas in the two active senses — the volitional formations operative in dependent origination, and the kammic volitions in the fourth aggregate — construct the sankharas in the passive sense: “They construct the conditioned; therefore they are called volitional formations. And what are the conditioned things they construct? They construct the body, feeling, perception, volitional formations, and consciousness; therefore they are called volitional formations” (SN XXII.79).”
The word ‘cetasika’ has the literal, (non- specialized Abhidhamma sense) of pertaining to the cetas (the mind) = ‘mental’
No. It all depends on how cetasika is translated. Cetasika can simply mean ‘mental factor’, i.e., something the mind depends upon. This does not automatically make cetasika to be sankhara aggregate. In Abhidhamma, perception & feeling are two of 52 cetasika.
If that is so , it means feeling perception are mano sense objects but volition (4th sankhara) isnt ?
They meditate observing an aspect of the mind—keen, aware, and mindful, rid of desire and aversion for the world.
citte cittānupassī viharati ātāpī sampajāno satimā, vineyya loke abhijjhādomanassaṁ;
No. Anything mental (feeling, perception, sankhara, consciousness) can be a mano sense object. Even Nibbana, which is not mental, is a mano sense object. That is why the mano sense objects are called “dhamma”.
It seems cittasankhara means what conditions the citta. For example because of feeling & perception, the citta thinks, has greed & proliferates:
What you feel, you perceive. What you perceive, you think about. What you think about, you proliferate.
When you experience a pleasant feeling, if you approve, welcome, and keep clinging to it. So the underlying tendency to greed underlies that.
When you experience a painful feeling, if you sorrow and wail and lament, beating your breast and falling into confusion, the underlying tendency to repulsion underlies that.
The above is the first thing I ever learned in Buddhism in the first Dhamma talk I ever listened to.
If you do not understand feeling and what it can condition/cause, you cannot understand the Buddha’s teaching. AN 3.61 says:
It’s for one who feels that I declare: ‘This is suffering’ … ‘This is the origin of suffering’ … ‘This is the cessation of suffering’ … ‘This is the practice that leads to the cessation of suffering’.
That cittasaṅkhāro is “volition” seems like an interpretation. It is the standard Theravada interpretation. However, based on the EBTs, this interpretation is questionable and subject to debate. For Bhikkhu Bodhi and most of Theravada, cittasankhara means “volition”. This is also the Abhidhamma view and I assume also the Commentary view. The Buddha never taught Dhamma is a dogma. The responsibility falls upon you to study and realise, as the Buddha taught. With metta