In the Buddha's Words - Bhikkhu Bodhi [165]
An entire chapter of the Saṃyutta Nikāya, the Nidānasaṃyutta (chapter 12), is devoted to dependent origination. The doctrine is usually expounded as a sequence of twelve factors joined into a chain of eleven propositions; see Text IX,4(4)(a). A Buddha discovers this chain of conditions; after his enlightenment, his mission is to explain it to the world. Text IX,4(4)(b) declares the sequence of conditions to be a fixed principle, a stable law, the nature of things. The series is expounded in two ways: by way of origination (called anuloma or forward order), and by way of cessation (called paṭiloma or reverse order). Sometimes the presentation proceeds from the first factor to the last; sometimes it begins at the end and traces the chain of conditions back to the first. Other suttas pick up the chain somewhere in the middle and work either backward to the end or forward to the front.
The Nikāyas themselves do not give any systematic explanation of dependent origination in the way one might expect a college textbook to do. Thus, for a clear explanation, we must rely on the commentaries and expository treatises that have come down from the Early Buddhist schools. Despite minor differences in details, these concur on the general meaning of this ancient formula, which might be briefly summarized as follows: Because of (1) ignorance (avijjā), lack of direct knowledge of the Four Noble Truths, we engage in wholesome and unwholesome activities of body, speech, and mind; these are (2) volitional formations (saṅkhārā), in other words, kamma. Volitional formations sustain consciousness from one life to the next and determine where it re-arises; in this way volitional formations condition (3) consciousness (viññāṇa). Along with consciousness, beginning from the moment of conception, comes (4) “name-and-form” (nāmarūpa), the sentient organism with its physical form (rūpa) and its sensitive and cognitive capacities (nāma). The sentient organism is equipped with (5) six sense bases (saḷāyatana), the five physical sense faculties and the mind as organ of cognition. The sense bases allow (6) contact (phassa) to occur between consciousness and its objects, and contact conditions (7) feeling (vedanā). Called into play by feeling, (8) craving (taṇhā) arises, and when craving intensifies it gives rise to (9) clinging (upādāna), tight attachment to the objects of desire through sensuality and wrong views. Impelled by our attachments, we again engage in volitional actions pregnant with (10) a new existence (bhava). At death this potential for new existence is actualized in a new life beginning with (11) birth (jāti) and ending in (12) aging-and-death (jarāmaraṇa).4
From the above, we can see that the commentarial interpretation treats the twelve factors as spread out over a span of three lives, with ignorance and volitional formations pertaining to the past, birth and aging-and-death to the future, and the intermediate factors to the present. The segment from consciousness through feeling is the resultant phase of the present, the phase resulting from past ignorance and kamma; the segment from craving through existence is the karmically creative phase of the present, leading to renewed existence in the future. But existence is distinguished into two phases: one, called kamma-existence (kammabhava), constitutes the active side of existence and belongs to the causal phase of the present life; the other, called rebirth-existence (upapattibhava), constitutes the passive side of existence