(Last Updated on : 16-07-2015)
The later Upanishads are those of the few Upanishads which are written entirely or for the most part in verse, and belong to a period which is somewhat later, though still early, and probably pre-Buddhistic. These, too, are assigned to certain Vedic schools, though they have not always come down as portions of an Aranyaka. In this category one may include the Kathaka or Katha Upanishad
, the very name of which points to its connection with a school of the Black Yajur Veda
. The Svetasvatara Upanishad
and the Maha Narayana Upanishad which has come down as an appendix to the Taittiriya Aranyaka, are also counted among the texts of the Black Yajur Veda. The short, but most valuable Isa Upanishad
, which forms the last section of the Vajasaneyi Samhita, belongs to the White Yajur Veda. The Mundaka Upanishad
, and the Prasna Upanishad, half of which is in prose, half in verse, belongs to the Atharva Veda
Though these six Upanishads, too, contain the Vedanta philosophy
, here it is found interwoven to a great extent with Sankhya and Yoga
doctrines and with monotheistic views. All these texts show distinct signs of having been touched up. Though the two last-named texts must be among the latest offshoots of Vedic literature
, they too may still be classed together with the twelve earlier texts as Vedic Upanishads; and these fourteen Upanishads only can be used as sources for the history of the earliest Indian philosophy.
Though the remaining Upanishads are also attributed by tradition to one or other of the Vedic schools, only a few of them have any real connection with the Veda. Most of them are religious rather than philosophical works, and contain the doctrines and views of schools of philosophers and religious views of a much later period. Many of them are much more nearly related to the Puranas and Tantras chronologically as well as in content, than to the Veda.
This latest Upanishad literature may be classified as follows, according to its purpose and contents:
1) Those works which present Vedanta doctrines,
2) Those which teach Yoga
3) Those which extol the ascetic life (Sannyasa
4) Those which glorify Lord Vishnu
5) Those which glorify Lord Shiva
as the highest divinity,
6) Upanishads of the Saktas and of other more insignificant sects.
These Upanishads are written partly in prose, partly in a mixture of prose and verse, and partly in epic shloka. While the latter are on the same chronological level as the latest Puranas and Tantras, there are some works among the former which may be of greater antiquity, and which might consequently still be associated with the Veda. The following are probably examples of such earlier Upanishads- the Jabala Upanishad, which is quoted by Sankara as an authority, and which closes with a beautiful description of the ascetic named Paramahamsa; the Paramahamsa Upanishad, describing the path of the Paramahamsa still more vividly; the very extensive Subala Upanishad, often quoted by Ratnanuja, and dealing with cosmogony, physiology, psychology and metaphysics; the Garbha Upanishad, part of which reads like a treatise on embryology, but which is obviously a meditation on the embryo with the aim of preventing rebirth in a new womb ; and the Sivaite Atharvasiras Upanishad, which is already mentioned in the Dharmasutras as a sacred text, and by virtue of which sins can be washed away. Another factor which makes it difficult to determine the date of these Upanishads is the fact that they are often to be found in various recensions of very uneven bulk.
These non-Vedic Upanishads, as they may be called have come down in large collections which are not ancient as such. For the philosopher Sankara (about 800 A.D.) still quotes the Upanishads as parts of the Veda texts to which they belong; and even Ramanuja
(about 1100 A.D.) speaks of Chandogas, the Vajasaneyins or the Kausitaki when quoting the Upanishads of the schools in question. In the Muktika Upanishad, which is certainly one of the latest, it is written that salvation may be achieved by the study of the 108 Upanishads, and a list of 108 Upanishads is set forth, classified according to the four Vedas. Upanishads coming under the Rig Veda
, under the White Yajur Veda, under the Black Yajur Veda, under the Sama Veda
and under the Atharva Veda. This classification, however, can scarcely be based on an ancient tradition. All these Upanishads which are, properly speaking, non-Vedic are generally called Upanishads of the Atharva Veda. These were associated with the Atharva Veda because the authority of this Veda as sacred tradition was always dubious and it was, therefore, no difficult matter to associate all kinds of apocryphal texts with the literature belonging to the Atharva Veda. Furthermore, the Atharva veda was above all the Veda of magic and the secretiveness connected with it. The real meaning of "Upanishad"- and this meaning has never been forgotten- was "secret doctrine." What was more natural than that a large class of works which were regarded as Upanishads or secret doctrines, should be joined to the Atharva Veda, which itself was indeed nothing but a collection of secret doctrines.