If you want to learn something, read about it. If you want to understand something, write about it. If you want to master something, teach it.
有两种伟大的事物,我们越是经常、越是执著地思考他们,心中就越是充满永远新鲜、有增无减的赞美和敬畏,那就是我们头上的灿烂星空和我们内心的道德法则。 ——康德