In Buddhist philosophy, Buddha-nature is the potential for any sentient beings to become a Buddha. It is a common English translation for several related Mahayana Buddhist terms, including tathata ("suchness") but most notably tathāgatagarbha and buddhadhātu. Tathāgatagarbha means "the womb" or "embryo" (garbha) of the "thus-gone" (tathāgata), or "containing a tathāgata", while buddhadhātu literally means "Buddha-realm" or "Buddha-substrate". Buddha-nature has a wide range of (sometimes conflicting) meanings in Indian and later East Asian and Tibetan Buddhist literature. Broadly speaking, it refers to the belief that the luminous mind, "the natural and true state of the mind," the pure (visuddhi) mind undefiled by kleshas, is inherently present in every sentient being, and is eternal and unchanging. It will shine forth when it is cleansed of the defilements, c.q. when the nature of mind is recognised for what it is. The Mahāyāna Mahāparinirvāṇa Sūtra (written 2nd century CE), which was very influential in the Chinese reception of the Buddhist teachings, linked the concept of tathāgatagarbha with the buddhadhātu. The term buddhadhātu originally referred to relics. In the Mahāparinirvāṇa Sūtra, it came to be used in place of the concept of tathāgatagārbha, reshaping the worship of the physical relics of the Buddha into worship of the inner Buddha as a principle of salvation. The primordial or undefiled mind, the tathagatagarbha, is also equated with sunyata; with the alaya-vijñana ("store-consciousness", a yogacara concept); and with the interpenetration of all dharmas. The Chinese Yogacara school came to regard buddha-nature as an eternal ground and the ultimate source and support of all phenomenal reality. The Chinese Madhyamaka based its understanding of emptiness on the Indian sources and not on Daoist concepts which previous Chinese Buddhists had used, and sought to remove all ontological connotations of the term as a metaphysical reality.