Whose philosopy is called the Advaita ?

The philosophy of Advaita, or non-dualism, is attributed to Shankaracharya (also known as Adi Shankara). He expounded this doctrine from Kaladi, Kerala, rooting it in Vedanta and Upanishadic philosophy. Advaita emphasizes the non-dual nature of reality, asserting the oneness of the individual self (Atman) and the ultimate reality (Brahman) [3]. Shankaracharya is credited with consolidating and systematizing this school of thought, which uses the concept of 'Maya' (illusion) to explain the perceived world [4]. In contrast, Ramanujacharya (Option 1) founded the Vishishtadvaita school, or qualified monism, which challenged Shankara's absolute monism [2]. Nagarjuna (Option 3) was a Buddhist philosopher associated with the Madhyamaka school, and Vasumitra (Option 4) was a scholar of the Sarvastivada school of Buddhism. Thus, Shankaracharya is the definitive founder and exponent of Advaita Vedanta [4].

Sources

1. [1] History , class XI (Tamilnadu state board 2024 ed.) > Chapter 9: Cultural Development in South India > Advent of Adi Sankara > p. 131
2. [3] History , class XI (Tamilnadu state board 2024 ed.) > Chapter 9: Cultural Development in South India > 9.9 Sri Ramanujar (1017 - 1138) > p. 132
3. [4] History , class XI (Tamilnadu state board 2024 ed.) > Chapter 13: Cultural Syncretism: Bhakti Movement in India > 13.2 Spread of Bhakti Movement to the North India > p. 192
4. [2] https://www.britannica.com/biography/Shankara