It's pretty easy.I was thingking about a hint, but I find it unnecessary if you observe carefully.
And I would really appreciate if someone can tell me who said those words.
Answer
使用摩尔斯反代的替换密码,将.写作-,找到对应,得到明文为
Only those who take leisurely what the people of the world are busy about can be busy about what the people of the world take leisurely.
By Chang Ch'ao
选自林语堂译《幽梦影》