Juétiān 覺天 (Skt. Buddhadeva) was one of the four great Kaśmīra Vaibhāṣika masters whose views are extensively cited in the Mahāvibhāṣā (KR6l0010, T1545). Alongside Vasumitra (世友), Dharmatrāta (法救), and Ghoṣa (尊者瞿沙), he represents one of the four classical positions on how dharmas exist in the three times. Buddhadeva’s view is that the apparent difference of past, present, and future dharmas is merely relational (anyathā-anyathika) — they differ only by their relations to other dharmas, not in their intrinsic nature. No independent work of his survives; his positions are known only from quotations and refutations in the Mahāvibhāṣā and the Abhidharmakośa (KR6l0023).