Time of Composition
Historians and Indologists have put the date of composition of the Upanishads from around 800 - 400 B.C., though many of the verse versions may have been written much later. In fact, they were written over a very long period of time and do not represent a coherent body of information or one particular system of belief. However, there is a commonality of thought and approach.

The Main Books
Although there are more than 200 Upanishads, only thirteen have been singled out as presenting the core teachings. They are the Chandogya, Kena, Aitareya, Kaushitaki, Katha, Mundaka, Taittriyaka, Brihadaranyaka, Svetasvatara, Isa, Prasna, Mandukya and the Maitri Upanishads. One of the oldest and longest of the Upanishads, the Brihadaranyaka says:

"From the unreal lead me to the real!
From darkness lead me to light!
From death lead me to immortality!"

The crux of the Upanishads is that this can be achieved by meditating with the awareness that one's soul ("atman") is one with all things, and that "one" is the Absolute ("Brahman"), which becomes the "all".

Who wrote the Upanishads?
The authors of the Upanishads were many, but they were not solely from the priestly caste. They were poets prone to flashes of spiritual wisdom, and their aim was to guide a few chosen pupils to the point of liberation, which they themselves had attained. According to some scholars, the main figure in the Upanishads is Yajnavalkya, the great sage who propounded the doctrine of "neti-neti", the view that "truth can be found only through the negation of all thoughts about it". Other important Upanishadic sages are Uddalaka Aruni, Shwetaketu, Shandilya, Aitareya, Pippalada, Sanat Kumara. Many earlier Vedic teachers like Manu, Brihaspati, Ayasya and Narada are also found in the Upanishads.

THE UPANISHADS

The upanishads are expositions of doctrine, typically found in the concluding portions of the brAhmaNas and AraNyakas of the four vedas. A number of upanishads are extant today, with commentaries on them by representatives of various schools of vedAnta. The upanishads are not to be seen as uniform books - each text is connected to the veda in which it occurs, and the upanishadic teaching is often presented in the context of a particular vedic hymn or ritual. In the vedAnta traditions, the upanishads are referred to as the Sruti prasthAna, i.e. revealed scripture, from which knowledge of brahman is obtained.

The Principal upanishads: The upanishads that have been commented upon by Sankara and other teachers have have acquired extra significance as the principal or more or less "canonical" upanishads. These are:

aitareya (Rg veda)
bRhadAraNyaka (Sukla yajurveda)
ISa (Sukla yajurveda)
taittirIya (kRshNa yajurveda)
kaTha (kRshNa yajurveda)
chAndogya (sAma veda)
kena (sAma veda)
muNDaka (atharva veda)
mANDUkya (atharva veda)
praSna (atharva veda)

These ten are the most important and principal texts. Modern scholars believe that these also represent the oldest of the upanishadic texts. Others add the kaushItakI and SvetASvatara upanishads to the list of principal upanishads, and some add the maitrAyaNI too.

Other upanishads: A number of other upanishads are extant today. The Indian traditions regard the upanishads as Sruti, which is timeless, eternal, and apaurusheya (unauthored). Hence, finding dates of composition for the various upanishads is a meaningless non-issue to them. Some of the texts that are called upanishads may not be accepted by specific traditions. However, this is really a question of acknowledging the Sruti status of a given text, not one of finding a date of composition. Modern scholars attempt to fix periods of composition for all these texts. Needless to say, the date of composition of these texts, including those of the principal upanishads, is of no real concern to the vedAnta traditions.

It has become popular to classify the upanishads in terms of the subject matter they cover. Thus, we have a large number of upanishads dealing with general topics of vedAnta, in addition to those that teach yoga, and those that detail the rules of sam.nyAsa. The upanishads that tend to concentrate on one of the Great Deities of Hinduism are usually classified as Saiva, vaishNava and SAkta upanishads.

A list of 108 upanishads as found in the muktikopanishad is given in the table below. The yajurveda column has two rows under each heading - kRshNa yajurveda texts are in the upper row, and Sukla yajurveda texts in the lower one.

Comments:

The classification of the upanishads on the basis of their subject matter seems reasonable, and other than the 10 principal ones, most of the upanishads quoted by the earliest commentators fall under the sAmAnya vedAnta category. However, some upanishads could possibly be classified under more than one heading. For example, varAha and pASupatabrahma upanishads are classified as yoga upanishads and not as vaishNava and Saiva upanishads respectively. Similarly, gaNapati upanishad is included as a Saiva upanishad, while skanda upanishad is not. Also, hamsa upanishad is called a yoga upanishad and not a sam.nyAsa upanishad, whereas paramahamsa is included as a sam.nyAsa upanishad. Similarly, the mahAvAkya upanishad and the brahmavidyA upanishad might also justifiably be included under the sam.nyAsa upanishads.

In any case, there seems to be a large overlap in subject matter between the "yoga" upanishads and the "sam.nyAsa" upanishads, pointing to the close relationship between yoga practice and sam.nyAsa as an institution. This also raises the possibility that the traditional association of yoga with sAm.khya in terms of the six darSanas may be slightly misleading. In this connection, it is interesting to note that the most important texts on the yoga system are by teachers of advaita vedAnta, from Sankara downwards, although all these commentators explain yoga more or less in sAm.khyan terms. Another interesting observation in this connection is that advaita vedAntins have completely internalized yoga practice as an aid to meditation and to realize the non-dual brahman.

The bulk of the vaishNava (9 out of 14), Saiva (6 out of 14) and SAkta (5 out of 9) upanishads are assigned to the atharva veda. However, it should be noted that the other three vedas also have a significant share of the "late" upanishad texts. Three SAkta upanishads are from the Rg veda, while there are no vaishNava upanishads and only one Saiva upanishad assigned to the Rg veda. Also, there are no Saiva or SAkta upanishads assigned to the Sukla yajurveda, but a substantial number of Saiva (5 out of 14) upanishads are from the kRshNa yajus. The SAkta upanishads are grouped together, although some teach worship of sarasvatI, lakshmI or pArvatI, and others describe SrIcakra upAsanA, where Sakti is identified with brahman Itself, rather than being the Sakti of one of brahmA, vishNu or Siva. Since the upanishads are associated with individual SAkhAs within each veda, it might be interesting to investigate the distribution of these upanishads further, and correlate them with the distribution of the vaidika SAkhAs among today's communities of vaishNavas, Saivas and SAktas.

The term Upanishad literally means, "sitting down near" and implies to sit near a spiritual teacher and learn from him the secret doctrines. The word Upanishad also means brahma-knowledge by which ignorance is loosened or destroyed. The Upanishads are also called the Vedanta. The literal meaning of Vedanta is 'the end of the Vedas'.

Originally there were 1180 Upanishads. Out of these, two hundred Upanishads made their proper appearance, and out of these two hundred, one hundred and eight Upanishads are now traceable. Of these thirteen are considered the principal Upanishads. The thirteen principal Upanishads are Isa, Katha, Ken, Prasna, Mundaka, Mandukya, Chandogya, Brhadaranyaka, Taittiriya, Aitareya, Svetasvatara, Kaivalya and Maitri.

The composition of the Upanishads marks a significant turning point in the development of Indian thought. They place meditation and mystical experience and philosophical interpretation of its significance at the heart of the religious quest. The aim of the Upanisadic teaching was not mere intellectual conviction of the truth but lived realization i.e. by strict personal effort that one can reach the truth. The Upanishads have always been quoted as the highest authority by all the Indian teachers, philosophers, and writers, whether dualists, qualified monist, or monist. President Radhakrishnan states:

“The Upanishads have shown an unparalleled variety of appeal during these long centuries and have been admired by different people, for different reasons, at different periods. They are said to provide us with a complete chart of the unseen Reality, to give us the most immediate, intimate and convincing light on the secret of human existence, to formulate, in Deussen's words, 'philosophical conceptions unequalled in India or perhaps anywhere else in the world,' or to tackle every fundamental problem of philosophy. All this may be so or may not be so. But of one thing there is no dispute, that those earnest spirits have known the fevers and ardours of religious seeking; They have expressed that pensive mood of the thinking mind which finds no repose except in the Absolute, no rest except in the Divine. The ideal which haunts the thinkers of the Upanishads, the ideal of man's ultimate beatitude, the perfection of knowledge, the vision of the Real in which the religious hunger of the mystic for divine vision and the philosopher's ceaseless quest for truth are both satisfied is still our ideal."”

According to Sri Chinmoy:

“The main longing of the Upanishads is for the ultimate Truth. This truth can be achieved by a genuine seeker who has many divine qualities and whose love of God preponderates over every other love. The seeker needs three things: vrata, self-dedication; krpa, grace; and sraddha, faith. These three qualities embodied, satya, Truth, is unmistakably attained.”

The symbolism used in the Rig Veda prevented the deep knowledge of Veda Samhitas from becoming widespread and the age of Rig Veda came to an end. Much later attempts were made to recover the knowledge of the Vedas and this lead to the emergence of the Upanishads.The Upanishads were discovered by personages called rishis or the seers (of thought). These spiritual principles were not created but discovered by the rishis. These truths are the utterances of the sages on the basis of their illumined experience. These illumined experiences of the sages were not ordinary perceptions, inference or reflections, but experiences of an independent reality which impinge on their consciousness. Sri Aurobindo states:

“The rishis of the Upanishads sought to recover the lost or waning knowledge of the Veda by meditation and spiritual experience and they used the text of the ancient Mantras as a prop and authority for their own intuitions and perception or else the Vedic word was a seed of thought and vision by which they recovered old truths in new forms. What they found, they expressed in other terms more intelligible to the age in which they lived."”

It is because the seers of the Upanishads reveal to us their pictures of the splendours of the unseen, that we are inspired to rise above the attractions and distractions of the materialistic life. These Upanishads have inspired generations of Indians with vision and strength by their spiritual power and their life-giving message. Swami Vivekananda declared:

“Strength, strength is what the Upanishads speak to me from every page. This is the one great thing to remember, it has been the one great lesson I have been taught in my life. Strength, it says, strength O man, be not weak. Are there no human weaknesses? Asks man. There are, says the Upanishads, but would more weakness heal them? Would you try to wash dirt with dirt? Will sin cure sin, weakness cure weakness? … Ay, it is the only literature in the world where you find the word 'Abhih', fearless, used again and again. In no other scripture in the world is this adjective applied either to God or man … And the Upanishads are the great mine of strength. Therein lies the strength enough to invigorate the whole world. The whole world can be vivified, made strong, energized through them. They will call with trumpet voice upon the weak, the miserable, and the downtrodden of all races, all creeds, all sects, to stand on their feet and be free. Freedom - physical freedom, mental freedom, and spiritual freedom are the watchwords of the Upanishads.”

In the Upanishads there is no single well-articulated system of thought. These are realizations of sages, which are solutions to different aspects of the philosophical problem and are joined together loosely. They deal with different concepts such as Brahman, Atman, the relation between Brahman, Atman & the world, the sacred relation of the human soul (Atman) and the ultimate reality, vidya (knowledge), avidya (ignorance), consciousness, karma, reincarnation. The central theme of the Upanishads is the concept of Brahman, the all-pervasive, immanent Supreme Being.

Courtesy --- P.V.KIRAN KUMAR