早些时候，学习知识技能主要通过师傅带徒弟的方式，要是没有合适的机会，一般很难有学习知识的途径。后来普及了学校教育，于是大多数人有了学习的机会，这主要通过老师的讲授以及自己阅读教科书和参考书。
      我没有经历过师傅带徒弟的时期。我上大学的时候正处于一个变革的时期——网络开始普及，但网络上的信息还不是很多。对于不懂的知识，除了可以和有限的几个人讨论（通常这有限的几个人也不是很清楚），就只能去图书馆查书了。如果能找到相关的书、相关的章节，要弄懂特定的知识是没有问题的，偶尔还会有别的收获。但是很多时候，找到相关的书、相关的章节本身就是一个挑战。有的时候，图书馆可能还没有适合自己的书，于是很多知识就似懂非懂地接受下来了。
      上了研究生以后，感觉很明显，网络的力量似乎一下就强大起来。主要是因为我知道了使用搜索引擎。自此以后，我的很多知识都来自网络了，关于Linux操作的、关于程序编写的，还有很多专业里的知识。在Wikipedia逐渐为人所知以后，里面的词条越来越多，也越来越完整，现在很多不明白的概念都可以在谷歌里搜索此概念+Wikipedia来获得相应信息了。在很多时候Wikipedia已经替代了书本（或者说手册）。
      而最近我发现，当越来越多的人开始使用博客和微博之后，通过这两个途径也可以学到不少知识（虽然有时候不太系统）。以前可以方便地访问陶哲轩的博客，从里面就可以学到不少数学知识。而我对于自由意志的认识是最近从微博上李淼老师对《<三体>的物理学》的讨论中获得的。
      总结起来就是，哪里的人多、活跃，那里就能成为学习的场所，并因此产生相应的学习模式。

2013年7月9日补记：

      再强调一下Wikipedia吧。Wikipedia于我的作用显然大于《大英百科全书》之类的砖头。一来，Wikipedia比较容易检索，这使得Wikipedia词条的错误可以容易地被发现和改正。二来，Wikipedia是免费的，这可以让每个人容易地获取知识，并参与到知识的传播中来。

      今天早上捐了100块给Wikipedia。本来我不喜欢做了什么事就到处说，但是收到Wikipedia的一封邮件，说鼓励我告诉感兴趣的朋友，这也是对Wikipedia的帮助。既然这样，我就把信的全文放在这里。

Thank you for donating to the Wikimedia Foundation. You are wonderful!

It's easy to ignore our fundraising banners, and I'm really glad you didn't. This ishow Wikipedia pays its bills --- people like you giving us money, so we can keep the sitefreely available for everyone around the world.

People tell me they donate to Wikipedia because they find it useful, and they trust it because even though it's not perfect, they know it's written for them. Wikipedia isn’t meant to advance somebody's PR agenda or push a particular ideology, or to persuade you to believe something that's not true. We aim to tell the truth, and we can do that because of you. The fact that you fund the site keeps us independent and able to deliver what you need and want from Wikipedia. Exactly as it should be.

You should know: your donation isn’t just covering your own costs. The average donor is paying for his or her own use of Wikipedia, plus the costs of hundreds of other people. Your donation keeps Wikipedia available for an ambitious kid in Bangalore who’s teaching herself computer programming. A middle-aged homemaker in Vienna who’s just been diagnosed with Parkinson’s disease. A novelist researching 1850s Britain. A 10-year-old in San Salvador who’s just discovered Carl Sagan.

On behalf of those people, and the half-billion other readers of Wikipedia and its sister sites and projects, I thank you for joining us in our effort to make the sum of all human knowledge available for everyone. Your donation makes the world a better place. Thank you.

Most people don't know Wikipedia's run by a non-profit. Please consider sharing this e-mail with a few of your friends to encourage them to donate too. And if you're interested, you should try adding some new information to Wikipedia. If you see a typo or other small mistake, please fix it, and if you find something missing, please add it. There are resources here that can help you getstarted. Don't worry about making a mistake:  that's normal when people first start editingand if it happens, other Wikipedians will be  happy to fix it for you.

I appreciate your trust in us, and I promise you we'll use your money well.

Thanks,
Sue

Sue Gardner
Executive Director,
Wikimedia Foundation

For your records: Your donation on 2013-07-08 was¥100.00.

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