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    书院是中国文化一个十分重要的机构，也是人类教育史上的一个有重大意义的制度。书院这个名词成为私人讲学的代表，是从朱熹开始的，但是用书院来称呼私人创办的学校则起自唐代。从唐末到20世纪初年，书院教育持续了1000多年。一个制度能维持这么久，那么它的贡献也就可想而知了。

    “私人讲学”这四个字其实是一个很现代的名词。因为在传统中国，公私的分别并不像现代这么清楚。唐末社会崩溃，世家大族早已陵夷，中央政令不行，原有的庙学教育也跟着衰落不振，于是便有了私人创办家族学校之举。其实私人教学，至少源始于孔子，但以家族之力来创办学校，招收学生，延聘师儒，却是以前少有的事。

    从传统教育的立场来说，私人兴学不外是在官学崩溃的时候，模仿其体制和规模，继续其功用，并没有取代官学的意思或目的。这样的私人教育当然缺乏现代人“公”“私”分明的特点。

    但是在发扬儒家的“为己之学”或宋明理学的思想方面，书院发挥了重要的作用。讲学的风气以及制度化当然要归功于书院，宋明理学或儒学的种种风尚及学派往往依附书院而发扬光大。这是中国教育制度史上十分光辉的发展。西洋中古学术的发展往往依附于大学，迨文艺复兴，则“学院”兴起，日渐取代大学。而到了启蒙时代，沙龙更成了新思想的温床。可见学术的发达往往和思想家荟萃的场所有千丝万缕的关系。从这个角度言之，书院是宋明以来儒学发达的制度上的保姆。

    政府对于书院所扮演的角色当然是很清楚的，因此有数次毁灭书院的纪录。也因此作为辅助官学教育的书院得以发展出其特立独行的性格，使它继续不断更新，创造新思潮，影响政治及社会。我们对东林书院和它所代表的实践精神的神往，无非是因为它所代表的正是传统中国读书人的独立理想。唯其独立而有尊严，唯其尊严而能赓续中国的人文传统。

    书院在各地发展的过程里，我们也可以看到它不断地和地方既有文化特色产生交流。中国有学术地理，可说是自宋代而开始。先此当然有学术与地方文化结合的现象，但中国疆土自元以来，扩张得特别快，再加上外族入主中国，所以在整合各种文化和民族传统的过程里，教育扮演了特别重要的角色。

    总之，书院教育舍弃在中国幅员扩张的过程时，追求政治上的齐一性，而选择文化上的包容性。从宋元以来，替中国维持它作为一个政治单位命脉的实在是这种文化上的弹性和教育、思想上的包容性。书院至少在充分官学化以前是这种文化命脉的主要机构。

（摘编自朱汉民 李弘祺主编《中国书院》）

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    Having a teenager at home can be a real headache. Many teenagers smoke, drink and even fight. They often do something dangerous.

    Earlier studies have shown that teenagers are more likely (可能) to make irrational decisions than people from any other age group, including children and adults. Is it that teenagers are too young to tell right from wrong? Not really. So what's the reason?

    According to Laurence, a teacher from a US university, the reason is that teenagers care a lot about how their peers (同龄人) view them—that is “peer influence”.

    As children enter their teenage years, they spend more time with their friends and classmates, and also they care more about what they think of them. This makes teenagers make decisions without thinking about the costs.

    In a test, a group of teenagers were asked to play a video driving game. When they played with their friends watching around them, they took more chances and drove more carelessly because that would increase their possibility of winning. But when they played alone, they drove more safely.

    Why do peers have such a big influence on teens' behavior?

As Laurence sees it, a teenager's brain is like a car with a good accelerator (油门) but a weak brake (刹车). The “accelerator” is fully developed by teenage years while the “brake” is still not fully developed. When teenagers are watched by their peers, they usually push hard on the accelerator. With their weak brake, it is likely that they are going to end up in an accident.

    But the good news is that a violent (暴力的)teenager doesn't necessarily become a violent adult. About two-thirds to three-quarters of violent youth grow out of it. “They get more self-controlled.”