Sarvâstivāda theorists describe the primary dharma which is qualified 所相法 by the four primary marks 四本相 of arising 生相, abiding 住相, changing 異相, and ceasing 滅相, and the four primary marks themselves, as mutual and simultaneous causes of one another. According to this theory, the functioning of the four primary marks enables the primary dharma to gather power in the future, to immediately begin to decay upon discharging and depleting its causal efficacy 作用, and to then revert to a dormant state of non-being in the past (Sarvâstivādin theorists envision time as flowing from the future, through the present, and into the past). On the one hand, because the four primary marks induce the four stages 分位 of alteration in the primary dharma, they are the cause 因 of the entirety of its activity. On the other hand, because the primary marks depend upon the coordinated activity of the primary dharma in order to obtain their characteristic function, they are also its effect 果. Therefore, the functioning of the four primary marks is the cause, as well as the result, of the activity of the primary factor.

As Dhammajoti describes (2003, 18–19), in general, for Sarvâstivāda theory, if A is the simultaneous cause of B, both A and B must exist at the same time—although they may belong to different time periods with respect to their own temporal frame of reference. That is, A and B may not arise—i.e., they may not initially become activated—within the same temporal dimension, but in order for A to be the simultaneous cause of B, A must exist at the same time as B.

One implication of the paradigmatically Sarvâstivāda tenet of simultaneity between cause and effect 因果同時 is that even if two conditioned dharmas become activated at different times, an already-active conditioned dharma can serve as the concurrent cause which initiates activity in another conditioned dharma in an immediately neighboring location. For example, primary dharma A that is abiding in the present moment (with respect to Aʼs temporal frame of reference) and currently discharging its causal efficacy to project a specific effect 引自果 is capable, as a result of this activity, of initiating the stage of arising 正生位 in another primary dharma B (located in the future with respect to Bʼs temporal frame of reference) by imparting causal power 勢力 to it, so that it can discharge causal efficacy to project its own effect during its stage of abiding 住位 in the subsequent moment. Sarvâstivādin theorist Saṃghabhadra 衆賢 explains that the simultaneous cause of the arising 倶生因 of a primary dharma in a cluster of nine dharmas 九法 consists in the concurrence of (1) the primary mark of arising, (2) the subsidiary mark 隨相 of the arising of arising 生生, along with (3) the convergence 和合 (sāmagrī) of causes and conditions 因緣 generated by the activity of neighboring clusters of nine dharmas. The presence of all three causal factors is required to fully activate a primary dharma such that it is ready to achieve its specific effect, whether physical, mental, or neither entirely physical nor entirely mental. Saṃghabhadra clarifies that the proximate causal condition 親緣 for a primary dharma to arise is the pure causal capability 功能 of its attendant mark of arising in the future (T⁰), although a primary dharma requires the assistance of contributory conditions 助緣 provided by other primary dharmas to begin to discharge causal efficacy by the outset of the present moment (T¹) during its stage of abiding (Brewster 2021, 30–31).

According to Sarvâstivāda doctrine, cause and effect, like all the functions of conditioned dharmas, are radically momentary, meaning they cease immediately upon arising 纔生卽滅. Causes must therefore remain extant until such time that their effect is realized in order to be considered actual causes. In this respect, in Sarvâstivāda causal theory, all causes exist simultaneously with their effects, not just a certain subset of causes. Saṃghabhadra recognizes that some causes do arise prior to their effects 前生因, although even these previously arisen causes persist in their activity long enough such that they remain present until their effect is eventually realized.

One important corollary of the Sarvâstivāda tenet of necessary simultaneity between cause and effect is that non-existent 無 (asat) sense objects cannot stimulate ordinary sense perception and mental cognition (see Cox 1988, 32). Sarvâstivāda theorists therefore reason that future 未來法 and past dharmas 過去法 must exist in the present to be able to engender present events: Future dharmas must already exist in the present to be able to bring about anticipations and precognitions of future events, and past dharmas must still exist in the present to potentiate present events, such as recollections of past events. In sum, while future and past dharmas do not arise at the same time as their present effects, insofar as they supply the contributory conditions 增上緣, they exist simultaneously with these present effects.

References:

Brewster, Ernest Billings. 2021. “Why Change Is the Only Constant: The Teachings on Momentariness Found in Xuanzangʼs Translation of the Abhidharma Treatises of Saṅghabhadra.” Korea Journal of Buddhist Studies 66 (0): 1–49.

Cox, Collett. 1988. “On the Possibility of a Non-existent Object of Perceptual Consciousness.” Journal of the International Association of Buddhist Studies 11 : 31–88.

Dhammajoti, K.L. 2003. “The Sarvāstivāda Doctrine of Simultaneous Causality.” Journal of the Centre for Buddhist Studies, Sri Lanka 1 : 17–54.

Pradhan, Prahlad, ed. 1967. Abhidharmakośa(bhāṣyam). Patna:  K.P. Jayaswal Research Institute.

Tanaka, Kenneth. 1985. “Simultaneous Relation (sahabhū-hetu): A Study in Buddhist Theory of Causation.” Journal of the International Association of Buddhist Studies 8 (1): 91–111.