Hello Pali friends,
In this compound the second part means 'recognition', and the first part can have two meanings - 'visual form' or 'form (in general)'.
Hence the first meaning of the compound, - "recognition of visual forms", a kind of "pa.tighasa~n~naa" - recognition of sense impressions.
603. “Pa.tighasa~n~naana.m attha"ngamaa”ti tattha katamaa pa.tighasa~n~naa? Ruupasa~n~naa saddasa~n~naa …pe… pho.t.thabbasa~n~naa– imaa vuccanti pa.tighasa~n~naayo. Imaa pa.tighasa~n~naayo santaa honti samitaa vuupasantaa attha"ngataa abbhattha"ngataa appitaa byappitaa sositaa visositaa byantiikataa. Tena vuccati “pa.tighasa~n~naana.m attha"ngamaa”ti.
"And what is recognition (sa~n~naa)? These six classes of recognition — recognition of form (ruupasa~n~naa), recognition of sound, recognition of smell, recognition of taste, recognition of tactile sensation, recognition of ideas: this is called recognition. From the origination of contact comes the origination of recognition. From the cessation of contact comes the cessation of recognition. And just this noble eightfold path is the path of practice leading to the cessation of recognition... The fact that pleasure & happiness arises in dependence on recognition: that is the allure of recognition. The fact that recognition is inconstant, stressful, subject to change: that is the drawback of recognition. The subduing of desire & passion for recognition, the abandoning of desire & passion for recognition: that is the escape from recognition...
Sattatthana sutta, SN XXII.57
The second meaning occurs in the description of transition from fourth to fifth jhana:
“Puna capara.m, po.t.thapaada, bhikkhu sabbaso ruupasa~n~naana.m samatikkamaa pa.tighasa~n~naana.m attha"ngamaa naanattasa~n~naana.m amanasikaaraa ‘ananto aakaaso’ti aakaasaana~ncaayatana.m upasampajja viharati. Tassa yaa purimaa ruupasa~n~naa saa nirujjhati. Aakaasaana~ncaayatanasukhumasaccasa~n~naa tasmi.m samaye hoti, aakaasaana~ncaayatanasukhumasaccasa~n~niiyeva tasmi.m samaye hoti. Evampi sikkhaa ekaa sa~n~naa uppajjati, sikkhaa ekaa sa~n~naa nirujjhati. Ayampi sikkhaa”ti bhagavaa avoca.
"And then, with the complete transcending of recognitions of [physical] form, with the disappearance of recognitions of sense impressions, and not heeding recognitions of diversity, thinking, 'Infinite space,' the monk enters & remains in the dimension of the infinitude of space. His earlier recognition of a refined truth of neither pleasure nor pain ceases, and on that occasion there is a recognition of a refined truth of the dimension of the infinitude of space. On that occasion he is one who is recognizing a refined truth of the dimension of the infinitude of space. And thus it is that with training one recognition arises and with training another recognition ceases.
Potthapada sutta, Digha Nikaya 9, DN 1.183
Vibhanga explains this meaning:
602. “Sabbaso ruupasa~n~naana.m samatikkamaa”ti tattha katamaa ruupasa~n~naa? Ruupaavacarasamaapatti.m samaapannassa vaa upapannassa vaa di.t.thadhammasukhavihaarissa vaa sa~n~naa sa~njaananaa sa~njaanitatta.m– imaa vuccanti “ruupasa~n~naayo”. Imaa ruupasa~n~naayo atikkanto hoti viitikkanto samatikkanto. Tena vuccati “sabbaso ruupasa~n~naana.m samatikkamaa”ti.
as relating to first four jhanas (ruupaa-vacara-samaapatti) or pleasant abiding in here and now (di.t.tha-dhamma-sukha-vihaara), which are synonyms. Arupa jhanas (on infinite space, etc.) are not called abiding in here and now.
This shows that in first four jhanas meditator clearly perceives the environment (form realm, ruupaa-vacara), with physical senses, while in formless (aruupa) jhanas such perception ceases.
This is corroborated by Samadhanga sutta, which describes how meditator suffuses this very body with rapture, please, and bright awareness. The metaphor:
"Just as if a man were sitting wrapped from head to foot with a white cloth so that there would be no part of his body to which the white cloth did not extend; even so, the monk sits, permeating his body with a pure, bright awareness. There is nothing of his entire body unpervaded by pure, bright awareness.
http://www.accesstoinsight.org/canon/su ... 5-028.html
shows that the physical body is meant here. Therefore, the meditator maintans the perception of the body in first four jhanas, though this perception markedly changes.
Then what about the cessation of physical perception which is described in Mahaparinibbana sutta:
"For at one time, Lord, Alara Kalama was on a journey, and he went aside from the highway and sat down by the wayside at the foot of a tree to pass the heat of the day. And it came about, Lord, that a great number of carts, even five hundred carts, passed by him, one by one. And then, Lord, a certain man who was following behind that train of carts, approached and spoke to him, saying: 'Did you, sir, see a great number of carts that passed you by?' And Alara Kalama answered him: 'I did not see them, brother.' 'But the noise, sir, surely you heard?' 'I did not hear it, brother.' Then that man asked him: 'Then, sir, perhaps you slept?' 'No, brother, I was not sleeping.' 'Then, sir, were you conscious?' 'I was, brother.' Then that man said: 'Then, sir, while conscious and awake you still did not see the great number of carts, even five hundred carts, that passed you by one after another, nor heard the noise? Why, sir, your very robe is covered with their dust!' And Alara Kalama replied, saying: 'So it is, brother.'
http://www.accesstoinsight.org/canon/su ... 6-sv0.html
Vimuttimagga (pp. 114-115) explains that meditator, moving from fourth jhana to the jhana of infinite space:
"... attains to the impeturbability of the formless attainment and the peacefulness of liberation. Alara Kalama and Uddaka Ramaputta when they entered the formless attainment, did not see nor hear those five hundred carts passing and repassing. Therefore, it is taught as the destruction of (sense) spheres; and thus, surpassing of all form perception is taught as the destruction of the form states and the perception of impact."
Visuddhimagga (X, 19) states the following:
"In fact it is because they [recognitions of sense impressions, pa.tighasa~n~naa] have not been abandoned already before this [immaterial attainment, aruupa jhana] that it was said by the Blessed One that sound is a thorn to one who has the first jhana (AN v,135).
And it is precisely because they are abandoned here that the imperturbability (see Vbh. 135) of the immaterial attainments and their state of peaceful liberation are mentioned (MN i,33), and that Alara Kalama neither saw the five hundred carts that passed close by him nor heard the sound of them while he was in an immaterial attainment (DN ii, 130)."
Here's the passage about "thorns" (ka.ntakaa):
“Dasayime, bhikkhave, ka.n.takaa. Katame dasa? Pavivekaaraamassa sa"nga.nikaaraamataa ka.n.tako, asubhanimittaanuyoga.m anuyuttassa subhanimittaanuyogo ka.n.tako, indriyesu guttadvaarassa visuukadassana.m ka.n.tako, brahmacariyassa maatugaamuupacaaro ka.n.tako, pa.thamassa jhaanassa saddo ka.n.tako, dutiyassa jhaanassa vitakkavicaaraa ka.n.takaa, tatiyassa jhaanassa piiti ka.n.tako, catutthassa jhaanassa assaasapassaaso ka.n.tako, sa~n~naavedayitanirodhasamaapattiyaa sa~n~naa ca vedanaa ca ka.n.tako raago ka.n.tako doso ka.n.tako moho ka.n.tako.
Kantaka sutta, AN v.135
So the cessation of physical perception is characteristic of formless jhanas.
In form jhanas this perception (ruupasaññaa) is preserved.