Yoga Sutras 4.22-4.26: Buddhi, Discrimination, and Liberation : Like the reflection on a mirror.

Like the reflection on a mirror: Think of the reflection on a mirror. There appears to be something there but try as you will, you cannot physically grasp the objects that appear in the mirror. They are there, yet are not there. However, by virtue of that reflection you are able to know, to experience. It is somewhat like that with consciousness, or purusha. It provides the light or life force so that the subtlest aspect of mind-stuff can operate, yet like with the mirror, it cannot itself be grasped and is unchanging. It is as if the consciousness, though unchanged, wraps itself around the subtle object called mind, and, in turn, all of the objects of the mind. This has been described in the beginning of the Yoga Sutras as the essential obstacle to be transcended, or disidentified with. (1.4).

The tool must be set aside: By realizing the extremely subtle nature of how the consciousness allows the mind-field to be active, it is evident that to know the absolute, unchanging Truth or Reality, one must let go of even this finest instrument. Through that letting go, the experience of the unchanging, eternal consciousness is there, standing alone, and this is the experience of Self-realization. It is the meaning of resting in one's True nature that is introduced in the beginning of the Yoga Sutras (1.3).

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