According to Buddhist texts, the entire universe, including the individual, is made up of different phenomena (dharma). Although all these phenomena of existence are reduced to transitory entities by the theory of anātman (no-self), Buddhism classifies these phenomena into different categories, including the conventionally accepted concept of "person." The three concepts of bases (āyatana), elements (dhātu), and aggregates (skandha; Pāli, khandha) constitute different schemes for classifying the various phenomena. Although the aggregates are nothing but a "convenient fiction," the Buddha nevertheless made frequent use of the skandha when asked to explain the elements at work in the individual.
According to this scheme, what is conventionally called a "person" can be understood in terms of five aggregates, the sum of which must not be mistaken for a permanent entity since beings are nothing but an amalgam of ever-changing phenomena. The five aggregates are variously translated as matter or form (rūpa); sensation, emotion, or feeling (vedanā); recognition or perception (saṃjñā); karmic activity, formation, force, or impulse (saṃskāra); and consciousness (vijñāna). Rūpa is made of four primary elements (mahābhūta): air, fire, water, and earth. It is also described as an amalgam of twenty-three secondary elements, which include the five sense organs, as well as their respective objects. Vedanā, on the other hand, refers to the actual experience of the senses, always qualified as being either pleasant, unpleasant, or neutral. The term saṃjñā is assigned to the mental faculty that imposes categories upon the sensory stimuli, which interprets what is sensed. The fourth aggregate, saṃskāra, is probably the hardest to grasp because of the various meanings associated with the term. It is a force, karmic energy, that generates all the other aggregates; the theory of pratĪtyasamutpĀda (dependent origination), for example, stipulates that on account of saṃskāra, vijñāna and the other links of the chain emerge. Saṃskāra can therefore be seen as the driving force, the fuel, or the energy that keeps the five aggregates bound together within the cycle of life and death (saṂsĀra). Saṃskāra is not only a causal factor; its signification includes everything that has been caused. Each of the five aggregates is therefore a saṃskāra in the sense that it is conditioned. The last aggregate is vijñāna (consciousness), the faculty responsible for apprehending what manifests itself through each of the six senses.
As with each of the links of the theory of dependent origination, the five aggregates are mutually dependent on one another. They need to be perceived from a cyclical perspective, where the last (vijñāna) is a key factor in the emergence of the first (rūpa). This causal process points to the everlasting cycle of saṃsāra as opposed to nirvĀṆa, which, in the TheravĀda tradition, is defined as a state totally devoid of the aggregates, beyond mind and matter.
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Boisvert, Mathieu. The Five Aggregates; Understanding Theravāda Psychology and Soteriology. Waterloo, ON: Wilfrid Laurier University Press, 1995.
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Gethin, R. M. "The Five Khandhas: Their Theatment [sic] in the Nikāyas and Early Abhidhamma." Journal of Indian Philosophy 52 (1986): 35–53.
Hamilton, Sue. Identity and Experience: The Constitution of the Human Being According to Early Buddhism. London: Luzac Oriental, 1996.