One knows that Feeling is there, regardless of what you think, do or perceive. It is there without your assistance, you are not needed for it; you can only know it because it is already there to be known, it is independent of you and you can never have it even if you wanted to.
You can think(foreground) I feel pleasure, because pleasurable feeling is there (background).
Itās the description of Dependent origination principal/paticcasamupada, āwith this, this isā ( when the background is, it determines the foreground or when the foreground is, it determines the background), and this principle is pretty much everywhere. The detailed paticcasamupada formulation is just the different ways one can understand the principleā¦
I.e. ,
Avijjapaccaya, bhikkhave, saį¹
khÄrÄ;saį¹
khÄrapaccayÄ( determines ) viƱƱÄį¹aį¹; viƱƱÄį¹apaccayÄnÄmarÅ«paį¹; nÄmarÅ«papaccayÄ saįø·Äyatanaį¹;saįø·ÄyatanapaccayÄ phasso; phassapaccayÄ vedanÄ;vedanÄpaccayÄ taį¹hÄ; taį¹hÄpaccayÄ upÄdÄnaį¹;upÄdÄnapaccayÄ bhavo; bhavapaccayÄ jÄti;jÄtipaccayÄ jarÄmaraį¹aį¹sokaparidevadukkhadomanassupÄyÄsÄ sambhavanti.Evametassa kevalassa dukkhakkhandhassasamudayo hoti. Ayaį¹ vuccati, bhikkhave,paį¹iccasamuppÄdoSn12.1
Then, bhikkhus, for the Bodhisattva VipassÄ«, who had gone to his dwelling, gone into solitude, in seclusion, this reflection arose in his mind: āIndeed, the world has entered into misery: one is born, ages, dies, passes away and is reborn. And yet one does not understand the escape from this suffering. Oh, when will the escape from this suffering be seen?ā Then, bhikkhus, for the Bodhisattva VipassÄ« there was this: āWhen there is what is there ageing-&-death, with the support of what, ageing-&-death?ā Then, bhikkhus, for the Bodhisattva VipassÄ«, because of attention from the origin, (yoniso manasikara) there was a breakthrough in understanding: āWhen there is birth ( foreground ) there is ageing-&-death ( background), with the support of birth, ageing-&-death.ā Then, bhikkhus, for the Bodhisattva VipassÄ« there was this: āWhen there is what is there birthā¦beingā¦ assumingā¦cravingā¦feelingā¦contactā¦ the six domainsā¦name-&-matteerā¦consciousness, with the support of what is there consciousness?ā Then, bhikkhus, for the Bodhisattva VipassÄ«, because of attention from the origin, there was a breakthrough in understanding: āWhen there is name-&-matter there is consciousness, with the support of name-&-matter, consciousness.ā Then, bhikkhus, for the Bodhisattva VipassÄ« there was this: āThis consciousness keeps coming back because of name-&-matter, it goes no further. In this way one can be born, one can age, one can die, one can pass away or one can be reborn, that is: with the support of name-&-matter, consciousness. With the support of consciousness, name-&-matterā¦" DN10
A demonstration of the simplified principal is in the buddhas questions ā¦in MN38
I recently recorded a dhamma talk, which might help clarify the principle. The speaker is Ajahn Nyanamoli, and itās called āDirectly Visibleā