Youth is not a time of life; it is a state of mind; it is not a matter of rosy cheeks, red lips and supple knees; it is a matter of the will, a quality of the imagination, a vigor of the emotions; it is the freshness of the deep springs of life.

Youth means a tempera-mental predominance of courage overtimidity, of the appetite for adventure over the love of ease. This often exists in a man of 60 more than a boy of 20.　

Nobody grows old merely by a number of years.　We grow old by deserting our ideals.Years may wrinkle the skin, but to give up enthusiasm wrinkles the oul.Worry, fear, self-distrust bows the heart and turns the spring back to dust.Whether 60 or 16, there is in every human being’s heart the lure of wonder, the unfailing childlike appetite of what’s next and the joy of the game of living.　

In the center of your heart and my heart there is a wireless station: so long as it receives messages of beauty, hope, cheer, courage and power from men and from the Infinite, so long are you young.When the aerials are down, and your spirit is covered with snows of cynicism and the ice of pessimism, then you are grown old, even at 20, but as long as your aerials are up, to catch waves of optimism, there is hope you may die young at 80.

PS：《Youth（青春）》——萨缪尔.厄尔曼    二战的麦克阿瑟将军在与日军在太平洋鏖战期间常以此文勉励自己。

青春不是生命中的一段时光，而是思想的一种状态；青春不在于粉红的脸颊，红润的嘴唇和有力的膝盖，而在于信念，一种想象力，一颗积极心。它是生命中最鲜艳的一抹春色。

青春意味着你的气质里融入了战胜怯懦的勇气，敢于追求自己渴望的自在生活。而这股力量60岁的老人却比20岁的少年拥有更多。

没有人会在短短几年中老去，除非他抛弃了自己的理想。时光会让皮肤起皱，但失去热情会让灵魂起皱。忧虑、恐惧、自卑只会使心中的绿色蒙上尘土。无论60岁还是16岁，所有人的心中都应该保持一颗永远的好奇心，一种孩子般对新事物的渴望和对生活乐趣的享受。

在你我的心中，有一个无线电站：只要它还在接收着来自周围人们和大千世界的所有关于美丽、希望、快乐、勇气的信息和电力，你就依然保持年轻。当它的天线下降，精神的沃土就会被玩世不恭与自怨自艾的冰雪掩埋，20岁风华也颓然苍老。然而当它的电线升起，乘着乐观的海浪，80岁离世也仍觉希望。