Saṃtāna

saṃtāna (P. santāna; T. rgyud/rgyun རྒྱུད་/རྒྱུན་; C. xiangzu 相續) is translated as "continuum," "continuity," etc. The term refers to "an uninterrupted sequence of cause and effects, especially a sequence of mental moments."

The Princeton Dictionary of Buddhism states:

Because there is nothing permanent in the mind and body, but there is continuity in the ways in which they are made manifest, they are described as a continuum. The term is used most commonly to refer to the mental continuum, both within a single lifetime and as it extends over many lifetimes.

The continuumm of psycho-physical factors (dharmas)

Charles Willemen states:

The factors or constituents of the dharma, the teachings, are also called dharma(s). Such dharmas are psychophysical factors, which flow according to the natural process of dependent origination. Dharma theory explains how the human being is a flux or continuum (santāna), without any permanent factor or soul (ātman).

Steven Goodman states:

Now, what do the Abhidharma traditions say is the actual condition of being human if this fixity [atman] is not the true picture? This fixity, this self, is a generalization, an abstraction or distortion, a surface presentation. The term that is used for characterizing living beings from the Abhidharma point of view is that we and our world is a streaming (saṃtāna); everything is a stream, a continuous flow of cooperating factors.

You will find lovely translations of Tibetan texts that state, “referring to my mental continuum,” which more precisely is “me as continuum,” not “my continuum.” It’s a continuum of dharmas. The flowing of these energy packets in a more or less disordered and anxious way is concretely how permanence, uniqueness, and autonomy as a fixation keeps the muddy stream going.

[With regards to the six channels of perception], sometimes this continuum or stream flows in a moment that we call seeing, and sometimes we call it hearing, smelling, tasting, touching, or “other.” This “other” (channel 6), which is all that is mental, all that is emotional, also includes all the great insights, such as “I like,” “I don’t like,” and “I remember.”

In fact, this continuum does not always consist of the same number of dharmas. According to the Abhidharma, the number of energy packets flowing at any time defines where—that is, in which realm—we are. The existential terms being or existing are not at all divorced from this deep analysis of flowing. “I flow, therefore I am.”

The cycle of birth and death

Bhikkhu Bodhi states:

But even death, the Buddha teaches, does not bring us to the end of dukkha, for the life process does not stop with death. When life ends in one place, with one body, the “mental continuum,” the individual stream of consciousness, springs up again elsewhere with a new body as its physical support. Thus the cycle goes on over and over—birth, aging, and death—driven by the thirst for more existence. The Buddha declares that this round of rebirths—called saṁsāra, “the wandering”—has been turning through beginningless time. It is without a first point, without temporal origin. No matter how far back in time we go we always find living beings—ourselves in previous lives—wandering from one state of existence to another. The Buddha describes various realms where rebirth can take place: realms of torment, the animal realm, the human realm, realms of celestial bliss. But none of these realms can offer a final refuge. Life in any plane must come to an end. It is impermanent and thus marked with that insecurity which is the deepest meaning of dukkha. For this reason one aspiring to the complete end of dukkha cannot rest content with any mundane achievement, with any status, but must win emancipation from the entire unstable whirl.

Effects of karma on the continuum

In the Buddhist view of karma, karmic actions are imprinted on the mental continuum (cittasaṃtāna), and these imprints, or seeds, will ripen at some future point when the appropriate conditions are assembled.

Bhikkhu Bodhi states:

The most important feature of kamma is its capacity to produce results corresponding to the ethical quality of the action... The [process] connecting actions with their fruits works on the simple principle that unwholesome actions ripen in suffering, wholesome actions in happiness. The ripening need not come right away; it need not come in the present life at all. Kamma can operate across the succession of lifetimes; it can even remain dormant for aeons into the future. But whenever we perform a volitional action, the volition leaves its imprint on the mental continuum, where it remains as a stored up potency. When the stored up kamma meets with conditions favorable to its maturation, it awakens from its dormant state and triggers off some effect that brings due compensation for the original action. The ripening may take place in the present life, in the next life, or in some life subsequent to the next. A kamma may ripen by producing rebirth into the next existence, thus determining the basic form of life; or it may ripen in the course of a lifetime, issuing in our varied experiences of happiness and pain, success and failure, progress and decline. But whenever it ripens and in whatever way, the same principle invariably holds: wholesome actions yield favorable results, unwholesome actions yield unfavorable results.

Sources

• Bodhi, Bhikkhu (1999), The Noble Eightfold Path: The Way to the End of Suffering (PDF) (Access to Insight ed.), Buddhist Publication Society 
• Buswell, Robert E.; Lopez, Donald S. (2014), The Princeton Dictionary of Buddhism, Princeton University 
• Goodman, Steven D. (2020), The Buddhist Psychology of Awakening: An In-Depth Guide to the Abhidharma (Apple Books ed.), Shambhala Publications 
• Willemen, Charles (2004), "Dharma and dharmas", in Buswell, Robert E., Encyclopedia of Buddhism, Vol. 1, MacMillan Reference USA, pp. 217–224