Overview
Manas (Pali: मनस्) is one of three overlapping terms used in the nikayas to refer to the mind, the others being citta and viññāṇa.
Comparison with citta and viññāṇa
Manas, citta, and viññāṇa are each sometimes used in the generic and non-technical sense of "mind" in general, and the three are sometimes used in sequence to refer to one's mental processes as a whole. Their primary uses are, however, distinct. In the distinction of Abhidhamma Pitaka of Theravada Buddhism, mana or mano is sort of the notion of mind as a whole, whereas a citta is each of instant steps or processes of mind, and viññāṇa is one of the several forms of citta, also being a step of a vithi or mental procedure, which is an orderly sequence of citta.
Relationship with thinking and volition
Manas often indicates the general thinking faculty. Thinking is closely associated with volitions, because mental activity is one of the ways that volitions manifest themselves: "Having willed, one acts through body, speech, and thoughts." Furthermore, willing is described in terms of deliberate thinking.
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