사수 (불교)

사수(捨受, 산스크리트어: upeksā-vedanā)는 괴롭지도 즐겁지도 않은 느낌 · 지각 · 정서로, 전통적인 표현으로는 열(悅)과 불열(不悅) 모두에 통하는 수(受)라 하는데, 대략적으로 말하자면, 마음(6식 또는 8식, 즉 심왕, 즉 심법)이 대상으로부터 괴로움(핍박)도 즐거움도 느끼지 않는 것이다.^[1] 불고불락수(不苦不樂受) 또는 평온(平穩, 팔리어: upekkhā, 산스크리트어: upekṣā)이라고도 한다.

엄밀히 말하면, 마음이 괴롭지도 즐겁지도 않은 느낌을 느끼는 것이 아니라 마음이라는 별개의 개체가 괴롭지도 즐겁지도 않은 느낌이라는 별개의 개체와 함께한 것, 즉, 두 개의 별개의 개체가 상응한 것이다. 불교 교의에 따르면, 무언가를 느끼는 것은, 느낌[受] 그 자체가 느낄[受] 뿐 따로 소유자가 있어 느끼는 것이 아니다.^[2] 그리고 이 느낌을 마음이 알아차림으로써, 즉, 이 느낌과 마음이 함께함으로써 느낌의 인식작용이 완성된다.^[3]^[4] 달리 말해, 인간은 색온 · 수온 · 상온 · 행온 · 식온의 5온으로 이루어져 있는데 색온(감각기관, 근)과 수온(느낌, 마음작용, 마음부수)과 식온(마음, 식)이 인식대상(경)과 화합할 때를, 즉, 4가지 조건 또는 인연이 만났을 때를 세간적인 표현 즉 엄밀한 표현이 아닌 일반적인 통용 표현으로 '무엇(인식대상)을 느낀다(색온+수온+식온)'고 말하는 것일 뿐이다.

불교에 따르면, 모든 마음은 반드시 느낌[受]을 동반한다.^[5](참고: 변행심소, 대지법) 즉, 크게 느낌을 세 가지로 구분할 때의 고수(괴로운 느낌) · 낙수(즐거운 느낌) · 불고불락수(괴롭지도 즐겁지도 않은 느낌, 무덤덤한 느낌, 그저 그런 느낌)의 3수(三受) 중 어느 하나와 반드시 상응한다. 또는, 3수를 더 세분한 고수 · 낙수 · 우수 · 희수 · 사수의 5수(五受) 중 어느 하나와 반드시 상응한다.

사수 즉 평온에는 크게 나누어 두 가지 수준이 있는데, 하나는 균형 · 평형 · 평정 · 좌로도 우로도 치우지치 않음 · 편견과 선호에 휩쓸리지 않음 · 좋음과 싫음에 휘둘리지 않음의 느낌의 뛰어난 상태 혹은 선한 상태의 사(捨)의 마음작용을 말한다. 이 마음작용은 수염(修厭) · 4무량심(四無量心) 등의 수행을 통해 개발하여야 하는 마음작용이다. 다른 하나는 괴롭지도 즐겁지도 않은 느낌, 좋지도 싫지도 않은 느낌, 그저 그런 느낌, 무덤덤한 느낌을 말한다. 이 마음작용은 자연히 존재하는 마음작용이다. 즉, 수행 등의 별다른 노력이 없어도, 지은 바 업에 따라 그 과보로서 자연히 느끼게 되는 느낌이다. 상좌부의 아비담마에서 해로운 과보의 마음과 원인 없는 유익한 과보의 마음에 속한 '평온이 함께한 안식' 등에서의 평온은 이 후자의 것을 뜻한다.^[5]

각주

↑ "捨" , 星雲. 《佛光大辭典》(불광대사전) 3판:
捨
梵語 upekṣā，巴利語 upekkhā 或 upekhā。音譯憂畢叉。意即平靜、無關心。(一)全稱行捨。俱舍宗以捨為遍一切善心共起的心所之一（十大善地法），唯識宗則列為善心所之一。即遠離惛沉之沉沒與掉舉之躁動，為不浮不沉，保持平靜、平等之精神作用或狀態。
關於捨之說法，俱舍論卷四、品類足論卷四皆謂，「捨」即平等正直、無警覺之性，而住於寂靜之心；於唯識大乘則認為依於精進、無貪、無瞋、無癡等四法，令心遠離掉舉等障而住於寂靜、無有雜染之心境。大毘婆沙論卷九十五、瑜伽師地論卷二十九以「捨」為七覺支中之捨覺支，為「奢摩他品」所攝。摩訶止觀卷三上，轉用此義而以捨為中道觀之異名。〔北本大般涅槃經卷三十、大毘婆沙論卷四十二、成唯識論卷六〕
(二)三受之一，五受之一。又稱捨受、不苦不樂受（梵 aduḥkhāsukha-vedanā）、不苦不樂覺。即非苦非樂的下意識之印象感覺。伴有捨受之禪定，稱捨俱定（巴 upekkhā-sahagata-samādhi），指色界第四禪定、四無色定及依捨俱欲界善淨心之欲界定。大毘婆沙論卷一一五以三受業配三界九地，廣果繫之善業及無色界繫之善業為順不苦不樂受業。又於八識中，前六識皆與三受相應，第七、第八兩識僅與捨受相應。成實論卷六辯三受品依雜阿含經卷十七之意，謂樂受中有貪使，苦受中有瞋使，不苦不樂受中有無明使。又不苦不樂受，其相寂滅，如無色定，以寂滅之故，煩惱細行，凡夫以為解脫，故以之為無明使。又巴利佛教中以捨為十波羅蜜之一。〔大毘婆沙論卷一四三、俱舍論卷三、成唯識論卷五、清淨道論卷三〕（參閱「三受」764）
(三)捨失之義。為「得」之對稱。即已得而今捨失之。與「不成就」同義。〔大毘婆沙論卷六十三、卷一一七、雜阿毘曇心論卷四、俱舍論卷二十一〕
(四)悉曇字砃（śa）。為悉曇五十字門之一、四十二字門之一。又作舍、賒、奢、𠾏、赦、柘、設、爍、鑠。捨字門，一般多舉寂靜、寂靜不可得之義。蓋由梵語 śānta（賒多）、śānti（扇底）轉釋而來，意譯寂靜、寂滅；乃取自二字之字頭 śa（捨）。大日經疏卷二謂（大三九‧六五五中）：「奢字門，一切諸法本性寂故。」方廣大莊嚴經卷四、大方等大集經卷十、海意菩薩所問經卷十二、文殊師利問經卷上字母品等，皆以唱捨字時，出一切奢摩他毘鉢舍那之聲，此即由梵語 śamatha（止）vipaśyana（觀）轉釋而來。文殊問經字母品第十四載捨為信進念定慧（梵 śraddha-virya-smṛti-samādhi-prajñā）之義。北本大般涅槃經卷八解釋此字為遠離三箭之義。新華嚴經卷七十八載唱奢字時，入般若波羅蜜門。〔瑜伽金剛頂經釋字母品、大品般若經卷六、大智度論卷四十八、大日經疏卷七〕p5778
↑ (한국어) 각묵스님 옮김(2015) 《디가 니까야》 제2권 제22경 〈대념처경〉 초기불전연구원. pp.510~511.
II. 느낌의 관찰[受隨觀]
11. "비구들이여, 어떻게 비구가 느낌에서 느낌을 관찰하며[受隨觀] 머무는가?⁵⁵⁵⁾ 비구들이여, 여기 비구는 즐거운 느낌⁵⁵⁶⁾을 느끼면서 즐거운 느낌을 느낀다.'고 꿰뚫어 안다.⁵⁵⁷⁾ 괴로운 느낌을 느끼면서 '괴로운 느낌을 느낀다.'고 꿰뚫어 안다. 괴롭지도 즐겁지도 않은 느낌을 느끼면서 '괴롭지도 즐겁지도 않은 느낌을 느낀다.'고 꿰뚫어 안다.
⁵⁵⁵⁾ "이처럼 세존께서는 물질의 명상주제를 설하신 뒤 이제 정신의 명상주제를 설하시면서 「제석문경」(D21)의 주석에서처럼 느낌으로 정신적인 명상주제를 설하신다. 왜냐하면 감각접촉이나 마음으로 그것을 설하게 되면 [명상주제가] 분명해지지 않는 것이 마치 암흑과도 같기 때문이다. 그러나 느낌들의 일어남은 아주 분명하기 때문에 느낌으로 설하면 [명상주제가] 분명해지기 때문이다. 거기서 '두 가지 명상주제가 있나니 물질적인 명상주제와 정신적인 명상주제이다.'라는 등의 설명은 「제석문경」에서 주석한 방법대로 알아야 한다."(DA.iii.774)
⁵⁵⁶⁾ "여기서 즐거운 느낌을(sukhaṁ vedanaṁ)이라는 것은 육체적이거나 정신적인 즐거운 느낌을 느끼면서 '즐거운 느낌을 느낀다.'고 꿰뚫어 안다는 뜻이다."(DA.iii.773)
⁵⁵⁷⁾ "여기서 '누가 느끼는가?' 一 어떤 중생이나 사람이 느끼는 것이 아니다. '느낌은 누구에게 속하는가?' 一 느낌은 어떤 중생이나 사람에게 속하는 것이 아니다.
'무슨 작용으로 느끼는가?' 一 [형상, 소리 등의] 토대(境)를 대상(vatthu-ārammaṇa)으로 하여 느낌이 있다. 그러므로 그는 이와 같이 꿰뚫어 안다. '이런저런 즐거운 토대 등을 대상으로 삼아 오직 느낌이 느낄 뿐이다(vedanāva vedayati). 그런 느낌의 일어남을 가져 나는 느낀다고 하는 단지 일상적인 어법(vohāra)이 있을 뿐이다.'라고. 이와 같이 감각토대를 대상으로 하여 느낌이 느낀다고 숙고하면서 '즐거운 느낌을 느낀다고 꿰뚫어 안다.'고 알아야 한다."(Ibid)
↑ Bhikkhu Bodhi & Allan R. Bomhard (2007). 《A Comprehensive Manual of Abhidhamma》. Charleston Buddhist Fellowship. p.37~38.
Five-sense-door adverting consciousness (pañcadvārāvajjanacitta): When an external sense object impinges on one of the five physical sense organs, before the appropriate sense consciousness can arise — for example, eye-consciousness seeing a form —, another consciousness must have arisen first. This consciousness is the fivesense- door adverting consciousness (pañcadvārāvajjanacitta), which has the function of adverting (āvajjana)³¹ to whatever object is presenting itself at one of the five sense doors (dvāra). This consciousness does not see, hear, smell, taste, or touch the object. It simply turns to the object, thereby enabling the sense consciousness to arise in immediate succession.³²
³¹ This is the turning of the mind towards an object. Āvajjana forms the first stage in the process of consciousness. When an object of the five physical senses is involved, it is called “five-sense-door adverting consciousness” (pañcadvārāvajjanacitta); in the case of a mental object, “mind-door adverting consciousness” (manodvārāvajjanacitta). Cf, Nyanatiloka, Buddhist Dictionary: Manual of Buddhist Terms and Doctrines (fourth revised edition [1980]), pp. 30—31.
³² A single unit of sense perception (for example, visual consciousness), being conditioned through a sense organ and its corresponding object, forms in reality an extremely complex process, in which all the single phases of consciousness follow one another in rapid succession, performing their respective functions, for example:
“As soon as a visible object has entered the range of vision, it acts on the sensitive eye-organ (cakkhu-pasāda), and, conditioned thereby, an excitation of the subconscious stream (bhavanga-sota) takes place.
“As soon, however, as subconsciousness is broken off, the functional mind element, grasping the object and breaking through the subconscious stream, performs the function of ‘adverting’ (āvajjana) the mind towards the object.
“Immediately thereupon, there arises at the eye-door, and based upon the sensitive eye-organ, the eye-consciousness, while performing the function of ‘seeing’ (dassana)…
“Immediately thereafter, there arises the mind-element, performing the function of ‘receiving’ (sampaṭicchana) the object of that consciousness…
“Immediately thereafter, there arises…the mind-consciousness element, while ‘investigating’ (santīraṇa) the object received by the mind-element…
“Immediately thereafter, there arises the functional, rootless mind-consciousness-element, accompanied by indifference, while performing the function of ‘determining’ (votthapana) the object…
“Now, if the object is large, then immediately afterwards there flash forth six or seven ‘impulsive moments’ (javana-citta), constituted by one of the eight wholesome (kusala) or twelve unwholesome (akusala) or nine functional (kiriya or kriyā) classes of consciousness.
“Now, if, at the end of the impulsive moments, the object at the five-sense doors is very large and at the mind-door clear, then there arises, once or twice, one of the eight root-accompanied kamma-resultant classes of consciousness of the sense-sphere, or one of the three rootless kamma-resultant mindconsciousness- elements… Because this consciousness, after the vanishing of the impulsive moments, possesses the faculty continuing with the object of the subconsciousness, taking the object of the subconsciousness as its own object, thereby, it is called ‘registering’ (tadārammaṇa, literally, ‘that object’ or ‘having that as object’).” (Visuddhimagga XIV, 115ff.)
If, however, the sense-object is weak, then it reaches merely the stage of “impulsion” (javana), or of “determining” (votthapana); if very weak, only an excitation of the subconsciousness takes place.
The process of the inner, or mind, consciousness, that is, without participation of the five physical senses, is as follows: in the case that the mind-object entering the mind-door is distinct, then it passes through the stages of “adverting at the mind-door” (manodvārāvajjana), “the impulsive stage,” and “the registering stage,” before finally sinking into the subconscious stream. Cf, Nyanatiloka, Buddhist Dictionary: Manual of Buddhist Terms and Doctrines (fourth revised edition [1980]), pp. 227—228.
↑
Mehm Tin Mon (2015). 《The Essence of Buddha Abhidhamma》. Third edition. Mehm Tay Zar Mon, Mya Mon Yadanar Literature. pp.37~38.
IMMORAL RESULTANT CONSCIOUSNESS (Akusala Vipāka Citta)
The seven akusala vipāka cittas are given the following symbols and names.
```
cakkhu      ghāna       kāya        santī
   —    —     —     —     ^     —     —
       sota       jivhā       sampa
```
1 Upekkhā-sahagataṁ cakkhuviññāṇaṁ
eye-consciousness accompanied by neutral feeling.
2 Upekkhā-sahagataṁ sotaviññāṇaṁ
ear-consciousness accompanied by neutral feeling.
3 Upekkhā-sahagataṁ ghānaviññāṇaṁ
nose-consciousness accompanied by neutral feeling.
4 Upekkhā-sahagataṁ jivhāviññāṇaṁ
tongue-consciousness accompanied by neutral feeling.
5 Dukkha-sahagataṁ kāyaviññāṇaṁ
body-consciousness accompanied by painful feeling.
6 Upekkhā-sahagataṁ sampaṭicchana-cittaṁ
receiving consciousness accompanied by neutral feeling.
7 Upekkhā-sahagataṁ santīraṇa-cittaṁ
investigating-consciousness accompanied by indifference.

Of the seven cittas mentioned above, the first five are known as pañca-viññāna, i.e., five cittas that are conscious of the five senses. The last two, i.e., sampaṭicchana-citta and santīraṇa-citta, represent two connecting stages in the process of cognition (awareness of an object).
For example, when a visible object appears in the eye, a series of consciousness has to arise and perish in order to see the object. First pañca-dvārāvajjana (five-door directing consciousness) directs the consciousness stream towards the object. Then cakkhu-viññāṇa (eye consciousness) sees the object and transmits it to the next consciousness.
Then sampaṭicchana (receiving consciousness) receives the sense object. Then santīraṇa (investigating consciousness) investigates the sense object. Then mano-dvārāvajjana (mind-door directing consciousness) determines the sense object whether it is good or bad. We are aware of the sense object roughly at this stage.
Similarly, when an audible voice strikes the eardrum, a series of consciousness, i.e., pañca-dvārāvajjana, sotaviññāṇa, sampaṭichana, santīraṇa, mano-dvārāvajjana, etc., has to arise and perish before we can hear the voice.
Thus sampaṭicchana-citta, santīraṇa citta together with pañca dvārāvajjana citta and mano-dvārāvajjana citta are essential for cognition of the senses at the five sense-doors (eye, ear, nose, tongue and body).
↑ ^가 ^나 Bhikkhu Bodhi & Allan R. Bomhard (2007). 《A Comprehensive Manual of Abhidhamma》. Charleston Buddhist Fellowship. p.35.
Accompanied by joy (somanassasahagata): The word somanassa, “joy,” is derived from su- = “pleasant” + manas- = “mind;” thus, it means, literally, a pleasant mental state. Somanassa is a type of feeling, specifically, pleasant mental feeling. All consciousness is accompanied by some feeling, which may be physical or mental, pleasant, painful, or neutral. Somanassa is a feeling that is mental rather than physical (bodily), and pleasant rather than painful or neutral. This feeling “accompanies” (sahagata) this type of consciousness in that it is inextricably blended with it, just as when the waters of two rivers meet, they blend together and cannot be distinguished. The Abhidhamma describes four cittas rooted in greed (lobha) and accompanied by a joyful mental feeling (somanassa). The other four cittas in this class are accompanied by equanimity (upekkhāsahagata). The word upekkhā is often used in the Pāḷi texts to signify the lofty spiritual quality of equanimity, or impartiality, the state of mind that cannot be swayed by biases and preferences. Here, however, the word is used simply to mean neutral feeling, a mental feeling that leans neither towards gladness nor sadness. In contrast to pleasant and painful feelings, which experience an object in diametrically opposed ways, upekkhā experiences the object in a neutral manner. Thus, upekkhā, or “equanimous feeling”, is also called “adukkhamasukhā vedanā,” “neither-painful- nor-pleasant feeling.”

[1] "捨" , 星雲. 《佛光大辭典》(불광대사전) 3판:
捨
梵語 upekṣā，巴利語 upekkhā 或 upekhā。音譯憂畢叉。意即平靜、無關心。(一)全稱行捨。俱舍宗以捨為遍一切善心共起的心所之一（十大善地法），唯識宗則列為善心所之一。即遠離惛沉之沉沒與掉舉之躁動，為不浮不沉，保持平靜、平等之精神作用或狀態。
關於捨之說法，俱舍論卷四、品類足論卷四皆謂，「捨」即平等正直、無警覺之性，而住於寂靜之心；於唯識大乘則認為依於精進、無貪、無瞋、無癡等四法，令心遠離掉舉等障而住於寂靜、無有雜染之心境。大毘婆沙論卷九十五、瑜伽師地論卷二十九以「捨」為七覺支中之捨覺支，為「奢摩他品」所攝。摩訶止觀卷三上，轉用此義而以捨為中道觀之異名。〔北本大般涅槃經卷三十、大毘婆沙論卷四十二、成唯識論卷六〕
(二)三受之一，五受之一。又稱捨受、不苦不樂受（梵 aduḥkhāsukha-vedanā）、不苦不樂覺。即非苦非樂的下意識之印象感覺。伴有捨受之禪定，稱捨俱定（巴 upekkhā-sahagata-samādhi），指色界第四禪定、四無色定及依捨俱欲界善淨心之欲界定。大毘婆沙論卷一一五以三受業配三界九地，廣果繫之善業及無色界繫之善業為順不苦不樂受業。又於八識中，前六識皆與三受相應，第七、第八兩識僅與捨受相應。成實論卷六辯三受品依雜阿含經卷十七之意，謂樂受中有貪使，苦受中有瞋使，不苦不樂受中有無明使。又不苦不樂受，其相寂滅，如無色定，以寂滅之故，煩惱細行，凡夫以為解脫，故以之為無明使。又巴利佛教中以捨為十波羅蜜之一。〔大毘婆沙論卷一四三、俱舍論卷三、成唯識論卷五、清淨道論卷三〕（參閱「三受」764）
(三)捨失之義。為「得」之對稱。即已得而今捨失之。與「不成就」同義。〔大毘婆沙論卷六十三、卷一一七、雜阿毘曇心論卷四、俱舍論卷二十一〕
(四)悉曇字砃（śa）。為悉曇五十字門之一、四十二字門之一。又作舍、賒、奢、𠾏、赦、柘、設、爍、鑠。捨字門，一般多舉寂靜、寂靜不可得之義。蓋由梵語 śānta（賒多）、śānti（扇底）轉釋而來，意譯寂靜、寂滅；乃取自二字之字頭 śa（捨）。大日經疏卷二謂（大三九‧六五五中）：「奢字門，一切諸法本性寂故。」方廣大莊嚴經卷四、大方等大集經卷十、海意菩薩所問經卷十二、文殊師利問經卷上字母品等，皆以唱捨字時，出一切奢摩他毘鉢舍那之聲，此即由梵語 śamatha（止）vipaśyana（觀）轉釋而來。文殊問經字母品第十四載捨為信進念定慧（梵 śraddha-virya-smṛti-samādhi-prajñā）之義。北本大般涅槃經卷八解釋此字為遠離三箭之義。新華嚴經卷七十八載唱奢字時，入般若波羅蜜門。〔瑜伽金剛頂經釋字母品、大品般若經卷六、大智度論卷四十八、大日經疏卷七〕p5778

[수념처1-3-디가니까야-각묵-2] (한국어) 각묵스님 옮김(2015) 《디가 니까야》 제2권 제22경 〈대념처경〉 초기불전연구원. pp.510~511.
II. 느낌의 관찰[受隨觀]
11. "비구들이여, 어떻게 비구가 느낌에서 느낌을 관찰하며[受隨觀] 머무는가?⁵⁵⁵⁾ 비구들이여, 여기 비구는 즐거운 느낌⁵⁵⁶⁾을 느끼면서 즐거운 느낌을 느낀다.'고 꿰뚫어 안다.⁵⁵⁷⁾ 괴로운 느낌을 느끼면서 '괴로운 느낌을 느낀다.'고 꿰뚫어 안다. 괴롭지도 즐겁지도 않은 느낌을 느끼면서 '괴롭지도 즐겁지도 않은 느낌을 느낀다.'고 꿰뚫어 안다.
⁵⁵⁵⁾ "이처럼 세존께서는 물질의 명상주제를 설하신 뒤 이제 정신의 명상주제를 설하시면서 「제석문경」(D21)의 주석에서처럼 느낌으로 정신적인 명상주제를 설하신다. 왜냐하면 감각접촉이나 마음으로 그것을 설하게 되면 [명상주제가] 분명해지지 않는 것이 마치 암흑과도 같기 때문이다. 그러나 느낌들의 일어남은 아주 분명하기 때문에 느낌으로 설하면 [명상주제가] 분명해지기 때문이다. 거기서 '두 가지 명상주제가 있나니 물질적인 명상주제와 정신적인 명상주제이다.'라는 등의 설명은 「제석문경」에서 주석한 방법대로 알아야 한다."(DA.iii.774)
⁵⁵⁶⁾ "여기서 즐거운 느낌을(sukhaṁ vedanaṁ)이라는 것은 육체적이거나 정신적인 즐거운 느낌을 느끼면서 '즐거운 느낌을 느낀다.'고 꿰뚫어 안다는 뜻이다."(DA.iii.773)
⁵⁵⁷⁾ "여기서 '누가 느끼는가?' 一 어떤 중생이나 사람이 느끼는 것이 아니다. '느낌은 누구에게 속하는가?' 一 느낌은 어떤 중생이나 사람에게 속하는 것이 아니다.
'무슨 작용으로 느끼는가?' 一 [형상, 소리 등의] 토대(境)를 대상(vatthu-ārammaṇa)으로 하여 느낌이 있다. 그러므로 그는 이와 같이 꿰뚫어 안다. '이런저런 즐거운 토대 등을 대상으로 삼아 오직 느낌이 느낄 뿐이다(vedanāva vedayati). 그런 느낌의 일어남을 가져 나는 느낀다고 하는 단지 일상적인 어법(vohāra)이 있을 뿐이다.'라고. 이와 같이 감각토대를 대상으로 하여 느낌이 느낀다고 숙고하면서 '즐거운 느낌을 느낀다고 꿰뚫어 안다.'고 알아야 한다."(Ibid)

[인식과정-Bodhi1-3] Bhikkhu Bodhi & Allan R. Bomhard (2007). 《A Comprehensive Manual of Abhidhamma》. Charleston Buddhist Fellowship. p.37~38.
Five-sense-door adverting consciousness (pañcadvārāvajjanacitta): When an external sense object impinges on one of the five physical sense organs, before the appropriate sense consciousness can arise — for example, eye-consciousness seeing a form —, another consciousness must have arisen first. This consciousness is the fivesense- door adverting consciousness (pañcadvārāvajjanacitta), which has the function of adverting (āvajjana)³¹ to whatever object is presenting itself at one of the five sense doors (dvāra). This consciousness does not see, hear, smell, taste, or touch the object. It simply turns to the object, thereby enabling the sense consciousness to arise in immediate succession.³²
³¹ This is the turning of the mind towards an object. Āvajjana forms the first stage in the process of consciousness. When an object of the five physical senses is involved, it is called “five-sense-door adverting consciousness” (pañcadvārāvajjanacitta); in the case of a mental object, “mind-door adverting consciousness” (manodvārāvajjanacitta). Cf, Nyanatiloka, Buddhist Dictionary: Manual of Buddhist Terms and Doctrines (fourth revised edition [1980]), pp. 30—31.
³² A single unit of sense perception (for example, visual consciousness), being conditioned through a sense organ and its corresponding object, forms in reality an extremely complex process, in which all the single phases of consciousness follow one another in rapid succession, performing their respective functions, for example:
“As soon as a visible object has entered the range of vision, it acts on the sensitive eye-organ (cakkhu-pasāda), and, conditioned thereby, an excitation of the subconscious stream (bhavanga-sota) takes place.
“As soon, however, as subconsciousness is broken off, the functional mind element, grasping the object and breaking through the subconscious stream, performs the function of ‘adverting’ (āvajjana) the mind towards the object.
“Immediately thereupon, there arises at the eye-door, and based upon the sensitive eye-organ, the eye-consciousness, while performing the function of ‘seeing’ (dassana)…
“Immediately thereafter, there arises the mind-element, performing the function of ‘receiving’ (sampaṭicchana) the object of that consciousness…
“Immediately thereafter, there arises…the mind-consciousness element, while ‘investigating’ (santīraṇa) the object received by the mind-element…
“Immediately thereafter, there arises the functional, rootless mind-consciousness-element, accompanied by indifference, while performing the function of ‘determining’ (votthapana) the object…
“Now, if the object is large, then immediately afterwards there flash forth six or seven ‘impulsive moments’ (javana-citta), constituted by one of the eight wholesome (kusala) or twelve unwholesome (akusala) or nine functional (kiriya or kriyā) classes of consciousness.
“Now, if, at the end of the impulsive moments, the object at the five-sense doors is very large and at the mind-door clear, then there arises, once or twice, one of the eight root-accompanied kamma-resultant classes of consciousness of the sense-sphere, or one of the three rootless kamma-resultant mindconsciousness- elements… Because this consciousness, after the vanishing of the impulsive moments, possesses the faculty continuing with the object of the subconsciousness, taking the object of the subconsciousness as its own object, thereby, it is called ‘registering’ (tadārammaṇa, literally, ‘that object’ or ‘having that as object’).” (Visuddhimagga XIV, 115ff.)
If, however, the sense-object is weak, then it reaches merely the stage of “impulsion” (javana), or of “determining” (votthapana); if very weak, only an excitation of the subconsciousness takes place.
The process of the inner, or mind, consciousness, that is, without participation of the five physical senses, is as follows: in the case that the mind-object entering the mind-door is distinct, then it passes through the stages of “adverting at the mind-door” (manodvārāvajjana), “the impulsive stage,” and “the registering stage,” before finally sinking into the subconscious stream. Cf, Nyanatiloka, Buddhist Dictionary: Manual of Buddhist Terms and Doctrines (fourth revised edition [1980]), pp. 227—228.

[인식과정-MTM1-4] Mehm Tin Mon (2015). 《The Essence of Buddha Abhidhamma》. Third edition. Mehm Tay Zar Mon, Mya Mon Yadanar Literature. pp.37~38.
IMMORAL RESULTANT CONSCIOUSNESS (Akusala Vipāka Citta)
The seven akusala vipāka cittas are given the following symbols and names.
cakkhu ghāna kāya santī — — — — ^ — — sota jivhā sampa

1 Upekkhā-sahagataṁ cakkhuviññāṇaṁ
eye-consciousness accompanied by neutral feeling.
2 Upekkhā-sahagataṁ sotaviññāṇaṁ
ear-consciousness accompanied by neutral feeling.
3 Upekkhā-sahagataṁ ghānaviññāṇaṁ
nose-consciousness accompanied by neutral feeling.
4 Upekkhā-sahagataṁ jivhāviññāṇaṁ
tongue-consciousness accompanied by neutral feeling.
5 Dukkha-sahagataṁ kāyaviññāṇaṁ
body-consciousness accompanied by painful feeling.
6 Upekkhā-sahagataṁ sampaṭicchana-cittaṁ
receiving consciousness accompanied by neutral feeling.
7 Upekkhā-sahagataṁ santīraṇa-cittaṁ
investigating-consciousness accompanied by indifference.

Of the seven cittas mentioned above, the first five are known as pañca-viññāna, i.e., five cittas that are conscious of the five senses. The last two, i.e., sampaṭicchana-citta and santīraṇa-citta, represent two connecting stages in the process of cognition (awareness of an object).
For example, when a visible object appears in the eye, a series of consciousness has to arise and perish in order to see the object. First pañca-dvārāvajjana (five-door directing consciousness) directs the consciousness stream towards the object. Then cakkhu-viññāṇa (eye consciousness) sees the object and transmits it to the next consciousness.
Then sampaṭicchana (receiving consciousness) receives the sense object. Then santīraṇa (investigating consciousness) investigates the sense object. Then mano-dvārāvajjana (mind-door directing consciousness) determines the sense object whether it is good or bad. We are aware of the sense object roughly at this stage.
Similarly, when an audible voice strikes the eardrum, a series of consciousness, i.e., pañca-dvārāvajjana, sotaviññāṇa, sampaṭichana, santīraṇa, mano-dvārāvajjana, etc., has to arise and perish before we can hear the voice.
Thus sampaṭicchana-citta, santīraṇa citta together with pañca dvārāvajjana citta and mano-dvārāvajjana citta are essential for cognition of the senses at the five sense-doors (eye, ear, nose, tongue and body).

[somanassasahagata-5] 가 ^나 Bhikkhu Bodhi & Allan R. Bomhard (2007). 《A Comprehensive Manual of Abhidhamma》. Charleston Buddhist Fellowship. p.35.
Accompanied by joy (somanassasahagata): The word somanassa, “joy,” is derived from su- = “pleasant” + manas- = “mind;” thus, it means, literally, a pleasant mental state. Somanassa is a type of feeling, specifically, pleasant mental feeling. All consciousness is accompanied by some feeling, which may be physical or mental, pleasant, painful, or neutral. Somanassa is a feeling that is mental rather than physical (bodily), and pleasant rather than painful or neutral. This feeling “accompanies” (sahagata) this type of consciousness in that it is inextricably blended with it, just as when the waters of two rivers meet, they blend together and cannot be distinguished. The Abhidhamma describes four cittas rooted in greed (lobha) and accompanied by a joyful mental feeling (somanassa). The other four cittas in this class are accompanied by equanimity (upekkhāsahagata). The word upekkhā is often used in the Pāḷi texts to signify the lofty spiritual quality of equanimity, or impartiality, the state of mind that cannot be swayed by biases and preferences. Here, however, the word is used simply to mean neutral feeling, a mental feeling that leans neither towards gladness nor sadness. In contrast to pleasant and painful feelings, which experience an object in diametrically opposed ways, upekkhā experiences the object in a neutral manner. Thus, upekkhā, or “equanimous feeling”, is also called “adukkhamasukhā vedanā,” “neither-painful- nor-pleasant feeling.”

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