Nisargadatta MaharajDesire not, fear not, observe the actual, as and when it happens, for you are not what happens, you are to whom it happens. Ultimately even the observer you are not. You are the ultimate potentiality of which the all-embracing consciousness is the manifestation and expression.

Nisargadatta Maharaj

Tattva Bodha
Knowledge of Reality, by Śaṅkarāchārya

Tattva Bodha Reference Materials:

Video/Audio Lectures

Swami Paramarthananda
36 classes (~30 - 55 mins each) 1, 2

Swami Anubhavananda
7 classes (~75 mins each)

Tattvabodha English 2 of 7 @ Prem Puri 2012

Swami Sarveshananda
27 classes (~45 - 60 mins each)

Swami Swatmananda
22 classes (~60 - 90 mins each)

20 vedanta fundas- full session with meditation

Swami Narasimhananda
12 classes (~60 - 90 mins each)

Introduction to Vedanta Tattvabodha Narasimhananda 2

Swami Viditatmananda
9 classes (search for "Tattvabodha" on the linked page)