<P> According to Nakamura, "there must have been an enormous number of other writings turned out in this period, but unfortunately all of them have been scattered or lost and have not come down to us today". In his commentaries, Shankara mentions 99 different predecessors of his Sampradaya . In the beginning of his commentary on the Brhadaranyaka Upanishad Shankara salutes the teachers of the Brahmavidya Sampradaya . Pre-Shankara doctrines and sayings can be traced in the works of the later schools, which does give insight into the development of early Vedanta philosophy . </P> <P> The names of various important early Vedanta thinkers have been listed in the Siddhitraya by Yamunācārya (c. 1050), the Vedārthasamgraha by Rāmānuja (c. 1050--1157), and the Yatīndramatadīpikā by Śrīnivāsa - dāsa . Combined together, at least fourteen thinkers are known to have existed between the composition of the Brahman Sutras and Shankara's lifetime . </P> <P> Although Shankara is often considered to be the founder of the Advaita Vedanta school, according to Nakamura, comparison of the known teachings of these early Vedantins and Shankara's thought shows that most of the characteristics of Shankara's thought "were advocated by someone before Śankara". Shankara "was the person who synthesized the Advaita - vāda which had previously existed before him". In this synthesis, he was the rejuvenator and defender of ancient learning . He was an unequalled commentator, due to whose efforts and contributions the Advaita Vedanta assumed a dominant position within Indian philosophy . </P> <P> Gaudapada (6th century) was the teacher of Govinda Bhagavatpada and the grandteacher of Shankara . Gaudapada uses the concepts of Ajativada and Maya to establish "that from the level of ultimate truth the world is a cosmic illusion," and "suggests that the whole of our waking experience is exactly the same as an illusory and insubstantial dream ." In contrast, Adi Shankara insists upon a distinction between waking experience and dreams . </P>

Who is who is the founder of advita philosophy
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