Sri Adi Shankaracharya is one of the earliest and most influential Advaitic teachers who contributed to simplify and spread Advaita Vedanta. He is well known for systematic reviews and commentaries on ancient Indian scriptures. He established his first institution in a place called Sringeri on the holy banks of River Tunga in India. Bhagavan Sri Ramana Maharishi stated that
Sri Adi Shankara’s Vivekachudamani (Crest Jewel of Discrimination) made of 580 verses, contains in detail all the points required for a seeker of liberation. He also commented that the entirety
of Advaita Vedanta can be found in verse 170 as follows,

‘In dreams, when there is no actual contact with the external world, the mind alone creates the whole universe consisting of experiencer etc. Similarly in the waking state also, there is no difference. Therefore, all this phenomenal universe is the projection of the mind.’