This volume primarily focuses upon the Yog c ra-Vijn nav din concepts of mind and its means of expression such as the various consciousnesses, the nature of the b jas, and the layavijn na. From this basis, related topics such as the nature of light, the simile of a river with respect to the flow of a consciousness-stream, and the n s that convey pr as, are explored. This allows consideration of the attributes of time and certain chakras that exist below the diaphragm. The 'soul' concept then comes into view and its relation to nyat is revealed."