A preparatory exercise, one I borrow from Sri Sadhu Om, that can lead to self-inquiry (atma vichara) involves asking: “Do I exist in the absence of this particular thing?” If I do exist in the absence of that particular thing, then that particular thing cannot be essential to my nature.

Then: Do I exist in the absence of the experience of the gross (or physical) body? Yes, clearly. I exist in the states of dream and deep sleep. In the first case, I, identifying myself with a dream character, believe that my body is a dream body. I, the dream character, have no experience of a physical body–none whatsoever. In which case, I continue to exist but without a physical body. Moreover, in the state of deep sleep, I continue to exist but without the experience of either the gross body or the dream body.

The same line of inquiry would show that I continue to exist in deep sleep in the absence of prana (the energy body) and mind.

Consequently, neither the gross body nor the dream body nor the pranic body nor the mental body can be essential to who I am.

“But how do you know that you continue to exist in the absence of either body and in the absence of the mind?” Because when I woke up and someone asked me, “How did you sleep?,” I can report: “I slept well.”

Let’s, in fact, consider further just this: “I slept.” When I say that I slept, I imply what is actually self-evident. It’s self-evident that I existed in sleep, for without my having existed in sleep, how could I, without any flinching or doubts, so readily say, “I slept”? I exist; I am.

Further, when I say, “I slept,” I also hint at what is equally self-evident: I was aware of the fact that I existed during deep sleep, for how else could I have known that I existed and thus how else could I have, without any doubt, have simply said, “I slept”?

Therefore, it’s self-evident (1) that I am and (2) that I am aware.

But without the appearance of any objects whatsoever in deep sleep, how could it be that I, as awareness (the subject), am aware of existence (an object)? This is not possible. In which case, it’s clear that being aware is identical with being itself and thus is nondual. In Sanskrit, this is satcit.

Through this inquiry, what has been discovered? First, that no body is a necessary condition for being-consciousness. And, second, that being-consciousness stands alone.