Unseen by the eye, highly subtile, and indescribable by words, it goes on in a round (of rebirths) among the creatures of the Earth, keeping before it that which is the root of action.
अग्राह्यं चक्षुषा सूक्ष्ममनिर्देश्यं च तद्गिरा। कर्महेतुपुरस्कारं भूतेषु परिवर्तते।१९।।