专家就是在非常狭窄的领域内犯过所有可能错误的人。
An expert is a person who has made all the mistakes that can be made in a very narrow field.
People are curious. A few people are. They will be driven to find things out, even trivial things. They will put things together, knowing all along that they may be mistaken.
如果你借给别人 20 美元，而他为了不还钱选择不再见你，那你们的关系就只值 20 美元。