When reading, Gai scholars should be ambitious, knowledgeable and persistent. Aspiring and unwilling to be indecent; If you have knowledge, you know that knowledge is infinite, and you dare not sell yourself short. Such as Hebo watching the sea, such as a well frog peeping into the sky, no one knows; Nothing is impossible if you have perseverance. These three are indispensable. At this time, the two brothers can only know a few things; As for ambition and perseverance, brothers just encourage.

-Quoted from The Complete Works of Zeng Gong.

Translation:

Scholars should be ambitious, knowledgeable and persistent in reading. Ambitious, unwilling to get dirty; If you are knowledgeable, you will know that learning is endless. If you dare not have a little experience, you will be complacent and complacent. For example, Hebo looks at the sea and the well frog looks at the sky. These people have no knowledge; Nothing is impossible with perseverance. These three pieces are indispensable. Dear brothers, you can't wait for knowledge now. As for ambition and perseverance, I hope you can work hard.

Central idea: learn to read.