《后汉书·列传·蔡邕列传下》
从前刘向上奏说 ：决策犹豫不决的人，为一般小人大开方便之门；养成了优柔寡断习惯的人，招来谄媚诽谤的坏家伙。 
时行则行，时止则止，消息盈冲，取诸天纪。
In the past, Liu Xiang played the piano and said: "Those who hesitate in making decisions open the door for ordinary people; those who develop the habit of indecision attract flatterers and slanderers."