《管子·心术下》
广加选择而自己不可陷于混乱，善于改变而自己不可陷于烦扰。一个坚持专一的君子，坚持专一而不放松，就能够统率万物，使日月与之同光，天地与之同理了。
慕选而不乱，极变而不烦，执一之君子执一而不失，能君万物，日月之与同光，天地之与同理。
To select widely but not to be confused, to be good at change but not to be disturbed. A gentleman who insists on being single-minded, insists on not relaxing, can lead all things, so that the sun and the moon will shine with him, and the heaven and the earth will be the same with him.