Mindstream

Mindstream (citta-santāna) in Buddhist philosophy is the moment-to-moment continuum (Sanskrit: saṃtāna) of sense impressions and mental phenomena, which is also described as continuing from one life to another.

Citta-saṃtāna (Sanskrit), literally "the stream of mind", is the stream of succeeding moments of mind or awareness. It provides a continuity of the personality in the absence of a permanently abiding "self" (ātman), which Buddhism denies. The mindstream provides a continuity from one life to another, akin to the flame of a candle which may be passed from one candle to another:

Indian Buddhists see the 'evolution' of mind i[n] terms of the continuity of individual mind-streams from one lifetime to the next, with karma as the basic causal mechanism whereby transformations are transmitted from one life to the next.

According to Waldron,

[T]he mind stream (santāna) increases gradually by the mental afflictions (kleśa) and by actions (karma), and goes again to the next world. In this way the circle of existence is without beginning."

The vāsanās (karmic imprints) provide the karmic continuity between lives and between moments. According to Lusthaus, these vasanas determine how one

...actually sees and experiences the world in certain ways, and one actually becomes a certain type of person, embodying certain theories which immediately shape the manner in which we experience.

Citta holds the semantic field of "that which is conscious", "the act of mental apprehension known as ordinary consciousness", "the conventional and relative mind/heart".Citta has two aspects: "...Its two aspects are attending to and collecting of impressions or traces (Sanskrit: vāsanā) cf. vijñāna."Saṃtāna or santāna (Sanskrit) holds the semantic field of "eternal", "continuum", "a series of momentary events" or "life-stream".

Citta is often rendered as sems in Tibetan and saṃtāna corresponds to rgyud, which holds the semantic field of "continuum", "stream", and "thread"--Citta-saṃtāna is therefore rendered sems rgyud. Rgyud is the term that Tibetan translators (Tibetan: lotsawa) employed to render the Sanskrit term "tantra".

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Wikipedia