SOURCE: Deussen, Paul. “Introduction to the Philosophy of the Upanishads.” In The Philosophy of the Upanishads, translated by A. S. Geden, pp. 1-50. Edinburgh: T. & T. Clark, 1906.

In the following excerpt, Deussen provides an overview of the Upanishads, discussing their history, composition, and ideological principles.

I. the Place of the Upanishads in the Literature of the Veda

1. the Veda and Its Divisions

It will be remembered that our earlier investigations led to a classification of Vedic literature into four principal parts, which correspond to the four priestly offices at the Soma sacrifice; these are the Rig, Yajur, Sâma, and Atharvaveda, each of which comprises a Samhitâ, a Brâhmana, and a Sûtra. The Brâhmana (in the wider sense of the term) is then further divided by the exponents of the Vedânta into three orders, which as regards their contents are for the most part...