1. 随着年岁的增长，精力日减，效率渐低，作风渐延：激情有失，理智有增。看来，这样的互易不可能总是得失相当的。但是，一定的年龄总有一定的长处。因此，可以告慰的是，即使你已度过了部分盛年，在未来的经历中，依然会有另一种盛年期的出现。某些重要的盛年期似乎在人生后期才达到顶峰。
2. 原始人一旦由于周围的许多令人愉快的情景而第一次开口大笑了，又由于笑对周围所产生的那些明显的愉快的效果，笑就开始具有了人类社会所特有的价值。具有用爽朗的笑声来传播愉快能力的人，开始比他的较为严肃、古板的同事更能享受到社会的优惠，从而使自己处于有利的地位。他成了个“善于交际的人”，在社交方面成了大家所推举的人，受到社会的喜爱。
3. 当今的世界，即非丝绸之路的时代，亦非马可波罗（Marco Polo）时代。从上海去东京，只需两个多小时。从中国去地球另一端的美国，也能在日历的同一天到达。昔日遥远的地理距离，被现代科学技术一下缩短到令人难以置信的程度。这是人类文明的共同成果。
1. As we grow older, our energy and efficiency decrease, and our style lengthens—passion loses, but reason increases. Such reciprocity, it seems, cannot always be equal. However, a certain age has certain advantages. The consolation, therefore, is that even if you have passed part of your prime, there will still be another prime in your future experience. Certain important prime years seem to peak later in life.
2. As soon as the primitive man had laughed for the first time because of the many pleasant circumstances around him, and because of the apparently pleasant effects of laughter on his surroundings, it began to take on the value unique to human society. The man who has the ability to spread pleasure with a hearty laugh begins to enjoy more social advantages than his more serious and staid colleagues, and thus puts himself in an advantageous position. He became a “people man”, socially preferred and liked by society.
3. Today’s world is neither the Silk Road nor the Marco Polo era. It takes just over two hours to go from Shanghai to Tokyo. From China to the United States, on the other side of the world, can also be reached on the same day of the calendar. The once distant geographical distance has been reduced to an incredible degree by modern science and technology. This is the common achievement of human civilization.
