Dear young friends, outside of being natural and pure, have you ever frequently wiped off the dusts in your mind?

In order to truly foster your own power, have you ever remained fearless in the face of pressure, rebelled against authority, and overthrown obstacles, so that you can deeply root yourself in the soil of history and culture to absorb its nutrients and hidden springs?

Have you ever carefully contemplated on the highest justice in human society or sought to realize this justice with all your might?

Have you ever aspired to seek mutual encouragement in a mentor or friend, or the acquaintance of noble friends or ancient sages, so that you could expand your heart and increase your resolve to see an even brighter future?

These all depend on your own effort, and you cannot take your youthful advantages for granted. You must know that the advantage of youth comes with being young, but will also fade away as youth does. “This fair face may outshine me today, when you reach the same old age I shall not yield.” In your middle ages, will you become that dispirited middle or old aged person whom you once despised? “The Qin people were too busy to feel sad for themselves, and left it to those of later times to feel sad for them. But if those people only felt sad and never reflected or learnt from their tragedies, those who then succeed their times will subsequently feel sad for them as well.” The greatest tragedy in the world is for people after our times to witness and feel sad for the tragedy which we have repeated.

── from Qingnian Yu Xuewen
(Youth and Knowledge)