Manduk: We generally tend to regard the waking world as true and the dreaming as not true for certain reasons. Manduk here, again, because it's very advanced approach to Advaita, it starts by equating the waking and dreaming. He says we'll come to the deep sleep where all dreams are switched off. So you have dreams, no dreams. But you, the one who watches these, you are the truth.
Swami Sarvapriyananda teaches one of the shortest and most profound upanishads accompanied by Gaudapada's Karika. This lecture covers Mantra 5-6.