We look in a mirror and the mirror will reflect back to us our face or our body, depending on the size of the mirror. The mirror will act as a reflecting surface.
It is said that each layer of our being acts as a reflecting surface for the layer more subtle to it.
For instance when meeting a friend, in just seeing their face, their eyes or even their skin, their vitality is reflected. We can ascertain their energy level, if they are getting enough sleep, if they are eating healthy, etc.
Similarly in the pace & quality of our breath, our state of mind is reflected. When the mind is panicked our breath accelerates. When our mind is overwhelmed the breath is constricted. When the mind is calm, the breath is flowing steadily and with ease.
In one’s state of mind our discernment is reflected. If the mind is foggy & confused, we are struggling in our ability to discern this from that. This may occasionally manifest on our Yoga mats when we get our left & right sides of the body confused or can’t discern if one hip is raised more than the other in a posture. But when the mind is clear, with a clear sense of direction, our inherent wisdom is finding it’s way through.
It is said that when our ability to discern is animated (sāttva buddhi) it is Self reflective, it is reflecting the Self. This is when consciousness, awareness, the soul’s reflection is perceived – in the qualities of clarity, focus, contentment, vitality, ease & freedom.
Inspired by (and for further understanding) –
Sutra 16, of Ātma Bodha of Shankaracharya translation & commentary by Shri Brahmananda Sarasvati –
The Self, the I AM, although it is All-pervading, is not cognized in everything. It is cognized only in Buddhi, Intelligence [Discernment], in the same way as a reflection is seen clearly only in a mirror, although it is falling equally on every object.
See also Edwin F. Bryant’s commentary & translation of Patanjali’s Yoga Sutras.