观天地,念非常。
观世界,念非常。
观灵觉,即菩提。
如是知识,得道疾矣。
— 释迦牟尼佛
《四十二章经》: 第十九章
Contemplate the heavens and earth, to be mindful of impermanence. Contemplate the world, to be mindful of impermanence. Contemplate spiritual awakening[‘s nature], which is Bodhi. With such knowledge, attain the path quickly.
— Śākyamuni Buddha
(Sūtra Of 42 Sections: 19th Section)