We are studying the Upanishads and the reason being that the Upanishads are the foundation of Vedantah.

And Upanishads are many in number. They are sometimes classified into major Upanishads and minor Upanishads.

If you see the number of Upanishads, they are

reported to be more than a thousand, though many are supposed to be lost now. But still,

we can find a list of, for example, 108 Upanishads. There is a minor Upanishad called the Muktik Upanishad

in which you find a list of 108 Upanishads.

But we generally study the major Upanishads.

This distinction between major Upanishad and minor Upanishads is not a traditional distinction.

It's just that Adi Shankaracharya, he selected 10, arguably 11 of the Upanishads

to write his famous commentaries on. And those Upanishads and his commentaries form the foundation

of the non-dual Vedantra tradition, the Adwaita Vedanthra tradition. Among those 10 Upanishads, I said arguably 11,

because sometimes Shwetāhāhāra Upanishad commentary is also, as part of the tradition, is regarded as Shankarachari's

commentary. But anyway, 10 are well known. And in those 10, a prominent Upanishad is the Isha Upanishad.

We have actually a verse which gives us the names of those ten prominent or major Upanishads.

Isha Kenakha Prasna, Mundamandukya titirihii, Aitareya, Chandogya, and Brihadaranyak

Akam Tha, Aisha, Kha, Prasna, Mundaka, Mandukya, Thaitiri Upanishad, Aitariya Upanishad, Chandogya,

and Brihadaraydhaa Upanishad, Chhandogya and Brihadaray Upanishad.

So you have 10.

If you notice, we have done, we have studied some of them.

We started out with the Mandukhi Upanishad and Mandukya Karika long ago, if somebody remembers.

And then we went on to the Kāhā Upanishad, then we studied the Mundak Upanishad, then we studied

the Khen Upanishad, and now we are at the Isha Upanishad.

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