The Vedas are divided mainly into two portions: the Karma-kanda and the Jnana - kanda--the work - portion and the knowledge - portion. To the Karma - kanda belong the famous hymns and the rituals of Brahmanas. Those books which treat of spiritual matters apart from ceremonials are called Upanishads. The Upanishads belong to the Jnana - kanda,or knowledge-portion. It is not that all the Upanishads were composed as a separate portion of the Vedas. Some are interspersed among the rituals, and at least one is in the Samhita,or hymn - portion. Sometimes the term Upanishad is applied to books which are not included in the Vedas--e.g. the Gita; but as a rule it is applied to the philosophical treatises scattered through the Vedas. These treatises have been collected, and are called the Vedanta.



The term Shruti--meaning "that which is heard"--though including the whole of the Vedic literature, is chiefly applied by the commentators to the Upanishads.

The Upanishads are said to be one hundred and eight in number. Their dates cannot be fixed with certainty--only it is certain that they are older than the Buddhistic movement. Though some of the minor Upanishads contain allusions indicating a later date, yet that does not prove the later date of the treatise, as in very many cases in Sanskrit literature,the substance of a book,though of very ancient date,receives a coating,as it were, of later events in the hands of the sectarians,to exalt their particular sect. of the Brahmanas or ritualistic writings; and the rest of the Upanishads are independent,not comprised in any of the Brahmanas or other parts of the Vedas; but there is no reason to suppose that they were entirely independent of other parts,for, as we well know, many of these have been lost entirely and many of the Brahmanas have become extinct. So it is quite possible that the independent Upanishads belonged to some Brahmanas,which in course of time fell into disuse, while the Upanishads remained. These Upanishads are also called Forest Books or Aranyakas.

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