Adi Shankara also known as Sankara Bhagavatpadacharya, and Adi Sankaracharya was an Indian philosopher who consolidated the doctrine of Advaita Vedanta, a sub-school of Vedanta. His teachings are based on the unity of the soul and Brahman, in which Brahman is viewed as without attributes. In the Smarta tradition, Adi Shankara is regarded as an incarnation of Shiva.

Shankara travelled across India to propagate his philosophy through discourses and debates with other thinkers. He founded four mathas (“monasteries”), which helped in the historical development, revival and spread of post-Buddhist Hinduism and Advaita Vedanta. Adi Shankara is believed to be the founder of the Dashanami monastic order and the Shanmata tradition of worship.

His works in Sanskrit, all of which are extant today, concern themselves with establishing the doctrine of Advaita (Nondualism). Adi Shankara quotes extensively from the Upanishads and other Hindu scriptures in support of his philosophy. Also, his works contain arguments against opposing schools of thought like Samkhya and Buddhism.

Life:

The traditional accounts of Adi Shankara’s life can be found in the Shankara Vijayams, which are poetic works that contain a mix of biographical and legendary material, written in the epic style. The most important among these biographies are the Madhaviya Sankara Vijayaṃ (of Madhava, c. 14th century), the Chidvilasiya Shankara Vijayaṃ (of Chidvilasa, c. between 15th century and 17th century), and the Keraliya Shankara Vijayaṃ (of the Kerala region, extant from c. 17th century).

Birth and childhood
Sankara was born to Kaippilly Sivaguru Nambudiri and Arya Antharjanam in the region of Kalady, in central Kerala. According to lore, it was after his parents, who had been childless for many years, prayed at the Vadakkunnathan temple, that Sankara was born.

His father died while Shankara was very young. Shankara’s upanayanaṃ, the initiation into student-life, was performed at the age of five. As a child, Shankara showed remarkable scholarship, mastering the four Vedas by the age of eight

Sannyasa
From a young age, Shankara was inclined towards sannyasa. But it was only after much compulsion that his mother gave him consent. Shankara then left Kerala and travelled towards North India in search of a Guru. On the banks of the Narmada River, he met Govinda Bhagavatpada, the disciple of Gaudapada. When Govinda Bhagavatpada asked Shankara’s identity, he replied with an extempore verse that brought out the Advaita Vedanta philosophy. Govinda Bhagavatapada was impressed and took Shankara as his disciple. The guru instructed Shankara to write a commentary on the Brahma Sutras and propagate the Advaita philosophy. Shankara travelled to Kashi, where a young man named Sanandana, from Choladesha in South India, became his first disciple. According to legend, while on his way to the Vishwanath Temple, Sankara came upon an untouchable accompanied by four dogs. When asked to move aside by Shankara’s disciples, the untouchable replied: “Do you wish that I move my ever lasting Ātman (“the Self”), or this body made of food?” Realizing that the untouchable was none other than god Shiva himself, and his dogs the four Vedas, Shankara prostrated himself before him, composing five shlokas known as Manisha Panchakam.

At Badari he wrote his famous Bhashyas (“commentaries”) and Prakarana granthas (“philosophical treatises”).

Meeting with Mandana Mishra
One of the most famous debates of Adi Shankara was with the ritualist Mandana Mishra. Mandana Mishra’s Guru was the famous Mimamsa philosopher, Kumarila Bhaṭṭa. Shankara sought a debate with Kumarila Bhaṭṭa and met him in Prayag where he had buried himself in a slow burning pyre to repent for sins committed against his Guru: Kumarīla Bhaṭṭa had learnt Buddhist philosophy incognito from his Guru in order to be able to refute it. Learning anything without the knowledge of one’s Guru while still under his authority constitutes a sin according to the Vedas. Kumarila Bhaṭṭa thus asked Adi Shankara to proceed to Mahismati (known today as Mahishi Bangaon, Saharsa in Bihar) to meet Mandana Mishra and debate with him instead.

Adi Shankara had a famous debate with Mandana Mishra in which the wife of Mandana Mishra, Ubhaya Bharati, was the referee. After debating for over fifteen days, Mandana Mishra accepted defeat. Ubhaya Bharati then challenged Adi Shankara to have a debate with her in order to ‘complete’ the victory. Later, Ubhaya Bharati concedes defeat in the debate and allows Mandana Mishra to accept sannyasa with the monastic name, Suresvaracharya as per the agreed rules of the debate.

Missionary tour
Adi Shankara then travelled with his disciples to Maharashtra and Srisailam. In Srisailam, he composed Shivanandalahari, a devotional hymn in praise of Shiva. The Madhaviya Shankaravijayam says that when Shankara was about to be sacrificed by a Kapalika, the God Narasimha appeared to save Shankara on Padmapada’s prayer to him. So Adi Shankara composed the Laksmi-Narasimha stotra. He then travelled to Gokarṇa, the temple of Hari-Shankara and the Mūkambika temple at Kollur. At Kollur, he accepted as his disciple a boy believed to be dumb by his parents. He gave him the name, Hastamalakacharya (“one with the amalaka fruit on his palm”, i.e., one who has clearly realised the Self). Next, he visited Śṛngeri to establish the Sharada Piṭham and made Toṭakacharya his disciple.

After this, Adi Shankara began a Dig-vijaya (missionary tour) for the propagation of the Advaita philosophy by controverting all philosophies opposed to it. He travelled throughout India, from the South to Kashmir and Nepal, preaching to the local populace and debating philosophy with Hindu, Buddhist and other scholars and monks along the way.

With the Malayali King Sudhanva as companion, Shankara passed through Tamil Nadu, Andhra Pradesh and Vidarbha. He then started towards Karnataka where he encountered a band of armed Kapalikas. King Sudhanva, with his army, resisted and defeated the Kapalikas. They safely reached Gokarna where Shankara defeated in debate the Shaiva scholar, Neelakanta.

Proceeding to Saurashtra (the ancient Kambhoja) and having visited the shrines of Girnar, Somnath and Prabhasa and explaining the superiority of Vedanta in all these places, he arrived at Dwarka. Bhaṭṭa Bhaskara of Ujjayini, the proponent of Bhedabeda philosophy, was humbled. All the scholars of Ujjayini (also known as Avanti) accepted Adi Shankara’s philosophy.

He then defeated the Jainas in philosophical debates at a place called Bahlika. Thereafter, the Acharya established his victory over several philosophers and ascetics in Kamboja (region of North Kashmir), Darada (Dabistan) and many regions situated in the desert and crossing mighty peaks, entered Kashmir. Later, he had an encounter with a tantrik, Navagupta at Kamarupa.

Accession to Sarvajnapitha
Adi Shankara visited Sarvajnapiṭha (Sharada Peeth) in Kashmir (now in Pakistan-occupied Kashmir). The Madhaviya Shankaravijayam states this temple had four doors for scholars from the four cardinal directions. The southern door (representing South India) had never been opened, indicating that no scholar from South India had entered the Sarvajna Pitha. Adi Shankara opened the southern door by defeating in debate all the scholars there in all the various scholastic disciplines such as Mimamsa, Vedanta and other branches of Hindu philosophy; he ascended the throne of Transcendent wisdom of that temple.

Towards the end of his life, Adi Shankara travelled to the Himalayan area of Kedarnath-Badrinath and attained videha mukti (“freedom from embodiment”). There is a samadhi mandir dedicated to Adi Shankara behind the Kedarnath temple. However, there are variant traditions on the location of his last days. One tradition, expounded by Keraliya Shankaravijaya, places his place of death as Vadakkunnathan temple in Thrissur, Kerala. The followers of the Kanchi kamakoti pitha claim that he ascended the Sarvajñapīṭha and attained videha-mukti in Kanchipuram (Tamil Nadu).

Dates
At least two different dates have been proposed for Shankara:

::~ 788–820 CE: This is the mainstream scholarly opinion, placing Shankara in mid to late 8th century CE. These dates are based on records at the Śṛṅgeri Śāradā Pīṭham, which is the only matha to have maintained a relatively unbroken record of its Acharyas; starting with the third Acharya, one can with reasonable confidence date the others from the 8th century down. The Sringeri records state that Sankara was born in the 14th year of the reign of “VikramAditya”, but it is unclear as to which king this name may refer. Though some researchers identify the name with Chandragupta II (4th. c. AD), modern scholarship accepts the Vikramaditya as being from the Chalukya dynasty of Badami, most likely Vikramaditya II (733–746 CE), which would place him in the middle of the 8th c. The date 788–820 is also among those considered acceptable by Swami Tapasyananda, though he raises a number of questions. It is also acceptable to Keay.

::~ 509–477 BCE: This dating, more than a millennium ahead of all others, is based on records of the heads of the Shankara Mathas at Dwaraka matha and Puri matha and the fifth Peetham at Kanchi. However, such an early date is not consistent with the fact that Sankara quotes the Buddhist logician Dharmakirti, who finds mention in Huen Tsang (7th c.). Also, his near-contemporary Kumarila Bhatta is usually dated ca. 8th c. AD. Most scholars feel that due to invasions and other discontinuities, the records of the Dwarka and Puri mathas are not as reliable as those for Sringeri.

Thus, while considerable debate exists, the pre-Christian Era dates are usually discounted, and the most likely period for Shankara is during the 8th c. CE.

Philosophy of Adi Shankara:

Shankara spread the tenets of Advaita Vedanta, the supreme philosophy of monism to the four corners of India with his ‘digvijaya’ (the conquest of the quarters). The quintessence of Advaita Vedanta (non-dualism) is to reiterate the truth of reality of one’s essential divine identity and to reject one’s thought of being a finite human being with a name and form subject to earthly changes.

According to the Advaita maxim, the True Self is Brahman (Divine Creator). Brahman is the ‘I’ of ‘Who Am I?’ The Advaita doctrine propagated by Shankara views that the bodies are manifold but the separate bodies have the one Divine in them.

The phenomenal world of beings and non-beings is not apart from the Brahman but ultimately become one with Brahman. The crux of Advaita is that Brahman alone is real, and the phenomenal world is unreal or an illusion. Through intense practice of the concept of Advaita, ego and ideas of duality can be removed from the mind of man.
The comprehensive philosophy of Shankara is inimitable for the fact that the doctrine of Advaita includes both worldly and transcendental experience.

Shankara while stressing the sole reality of Brahman, did not undermine the phenomenal world or the multiplicity of Gods in the scriptures.

Shankara’s philosophy is based on three levels of reality, viz., paramarthika satta (Brahman), vyavaharika satta (empirical world of beings and non-beings) and pratibhashika satta (reality).

Shankara’s theology maintains that seeing the self where there is no self causes spiritual ignorance or avidya. One should learn to distinguish knowledge (jnana) from avidya to realize the True Self or Brahman. He taught the rules of bhakti, yoga and karma to enlighten the intellect and purify the heart as Advaita is the awareness of the ‘Divine’.

Shankara developed his philosophy through commentaries on the various scriptures. It is believed that the revered saint completed these works before the age of sixteen. His major works fall into three distinct categories – commentaries on the Upanishads, the Brahmasutras and the Bhagavad Gita.

The most important of the works is the commentaries on the Brahmasutras – Brahmasutrabhashya – considered the core of Shankara’s philosophy of Advaita.

Mathas:

Adi Shankara founded four Maṭhas to guide the Hindu religion. These are at Sringeri in Karnataka in the south, Dwaraka in Gujarat in the west, Puri in Orissa in the east, and Jyotirmath (Joshimath) in Uttarakhand in the north. Hindu tradition states that he put in charge of these mathas his four main disciples: Sureshwaracharya, Hastamalakacharya, Padmapadacharya, and Totakacharya respectively. The heads of the mathas trace their authority back to these figures. Each of the heads of these four mathas takes the title of Shankaracharya (“the learned Shankara”) after the first Shankaracharya.

Source: http://en.wikipedia.org/ and From Manoj Sadasivan, for About.com
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