That which is always present in every experience, and is not experienced as an object and can never be experienced.

That which illuminates without the help of anything else and which can never be illuminated or objectified itself. A term for ātmā in the presence of anātmā.

It is important to realize that the witness neither experiences nor interprets. Just as light is not affected by what illuminates it, sākṣî always remains unaffected and unaffected by what it sees.

Consciousness, caitanya, when it pervades the mind and the body, is called sākṣî-caitanya. This is just another name to signify the penetration of the principle of consciousness into the body/mind. It is witnessing everything that happens in the body/mind and in the world.

Sākṣi caitanya, witness consciousness, is partless, unchanging, and devoid of qualities. It is never affected by any content or aspect of the body, mind, or world. Even though it seems to be limited to the body and mind, it is all-pervasive. It is eternal and ever-present, even when there is no body/mind.

The term sākṣiṇam (that which one witnesses) is sometimes used instead of anātmā when referring to the body-mind-sense complex, because the “proximity” of body and mind to ātmā makes it particularly difficult to distinguish from ātmā. Objects that are further away, such as clothes, chairs, etc., are much easier to distinguish as “not I” and therefore can be easily recognized as anātmā.

Our problem is that we want to be aware of consciousness. Therefore, we tend to treat it as an object that we can experience, when in fact it is just our svarūpa, our essential nature.