Trikaya

The Trikāya (Sanskrit: त्रिकाय, lit. "three bodies"; Chinese: 三身; pinyin: sānshēn; Japanese pronunciation: sanjin, sanshin; Korean pronunciation: samsin; Vietnamese: tam thân, Tibetan: སྐུ་གསུམ, Wylie: sku gsum) is a fundamental Buddhist doctrine that explains the multidimensional nature of Buddhahood. As such, the Trikāya is the basic theory of Mahayana Buddhist theology of Buddhahood.

This concept posits that a Buddha has three distinct kayas or "bodies", aspects, or ways of being, each representing a different facet or embodiment of Buddhahood and ultimate reality. The three are the Dharmakāya (Sanskrit; Dharma body, the ultimate reality, the Buddha nature of all things), the Sambhogakāya (the body of self-enjoyment, a blissful divine body with infinite forms and powers) and the Nirmāṇakāya (manifestation body, the body which appears in the everyday world and presents the semblance of a human body). It is widely accepted in Buddhism that these three bodies are not separate realities, but functions, modes or "fluctuations" (Sanskrit: vṛṭṭis) of a single state of Buddhahood.

The Trikāya doctrine explains how a Buddha can simultaneously exist in multiple realms and embody a spectrum of qualities and forms, while also seeming to appear in the world with a human body that gets old and dies (though this is merely an appearance). It is also used to explain the Mahayana doctrine of non-abiding nirvana (apratiṣṭhita-nirvana), which sees Buddhahood as both unconstructed (asaṃskṛta) and transcendent, as well as constructed, immanent and active in the world. This idea was developed in early Yogācāra school sources, like the Mahāyāna-sūtrālamkāra. The doctrine's interpretations vary across different Buddhist traditions, some theories contain extra "bodies", making it a "four body" theory and so on. However, the basic Trikāya theory remains a cornerstone of Mahayana and Vajrayana teachings, providing a comprehensive perspective on the nature of Buddhahood, Buddhist deities and the Buddhist cosmos. The Buddhist triple body theory was also adopted into Daoist philosophy and modified using Daoist concepts.