The Book of Throwing Blades in the Late Tang Dynasty

In the late Tang Dynasty, from the Great China period of Xuanzong to the early years of Yizong. It was the end of the "Reign of Dazhong", and under the afterglow of the prosperous age, the shadows of feudal towns, eunuchs, and party strife were already like twilight. In an era of irreversible collapse, how can individuals protect the "Tao" and "righteousness" in their hearts in the cracks of power?