Roots provide stability and access to nutrients for growth. Without roots a plant would tumble and wither. The same with a Taiji root, which is really just a willingness and tendency to sink and melt down into the ground. A content humbleness that gives itself to gravity in order to receive from Earth. The keen student often adopts a slouch, both of posture and of demeanour, in their efforts to develop a root. A Taiji master, on the other hand, with a well established root, never slumps because the upward flow of energy from that root, feeding spine and spirit, won't allow it.