The Vedanta Sutra and the Upanishads

The Vedanta Sutra is a philosophical treatise that doubles as a work of exegesis. It explores the relationship between our individual selves and this transcendent principle. The text at times seems almost to be written in code, with Shankara's authority looming over it. For this we need to know the Upanishads so well that even a single key word will be enough to tell us which text is at stake.