社会受到强烈冲击后，不但打破旧平衡，而且因惯性之故在新的平衡点也没有停下来，它越过新的平衡点继续向前冲击。社会既然离开了平衡点，就必然受到一个推它到平衡位置的社会反弹力的作用，使前运动停下来并反过来趋向平衡点。由于社会惯性又使社会在相反的方向偏离平衡，于是导致了社会振荡。社会受到强大冲击后总会发生振荡，这种振荡在英法资产阶级大革命中表现得显明显；在苏联和东欧的社会主义革命历史进程中又一次发生社会大振荡；东南亚金融危机也是由于受到冲击而引发的。社会振荡一般要多次反复才趋于稳定，如果偏高平衡点的社会在外力的控制下逐步地回复到平衡点，则社会也可以不经反复而实现稳定发展。中国在四项基本原则的指导下改革开放，使偏高平衡的社会可不经反复而达到平衡并实现稳定发展，这也是一种社会发展的规律。 The strong social impact not only shattered the old balance, but also stopped at the new equilibrium due to its inertia, and it continued to move forward beyond the new equilibrium. Since society has left the point of equilibrium, it must inevitably be subjected to a social rebound force that has pushed it to a balanced position, stopping the former movement and, in turn, toward the point of balance. Social inertia, in turn, distorts society in the opposite direction, resulting in social turmoil. There was always an oscillation after a strong social impact. Such oscillations were evident in the bourgeois revolution in Great Britain and France. There was another major social turmoil in the history of the socialist revolution in the Soviet Union and Eastern Europe. The financial crisis in Southeast Asia was also affected by the impact Caused. Generally speaking, social oscillations tend to be stable only after many iterations. If the society with a high balance gradually returns to its equilibrium under the control of external forces, the society can also achieve stable development without any repetition. Under the guidance of the four basic principles, China has made reform and opening up so that a society with a high balance can reach a balance and achieve stable development without repetition. This is also a law of social development.