The concept of law involves the union of primary rules of obligation with secondary rules of recognition, change, and adjudication.

领导力不在于掌控，而在于照顾你负责的人。

The best leaders are those who can see around corners and anticipate what's coming next.

At that age， I'd take any excuse to make estimates and do minor arithmetic. I'd calculate our gas mileage -- figure out useless statistics on things like grocery spending. I'd been hearing an ad campaign about smoking. I can't remember the details， but basically the ad said， every puff of a cigarette takes some number of minutes off of your life: I think it might have been two minutes per puff. At any rate， I decided to do the math for my grandmother. I estimated the number of cigarettes per days， estimated the number of puffs per cigarette and so on. When I was satisfied that I'd come up with a reasonable number， I poked my head into the front of the car， tapped my grandmother on the shoulder， and proudly proclaimed， "At two minutes per puff， you've taken nine years off your life！"

解释：对社会有用的，创作百篇也没有害处；对社会无用的，写一章也没有好处。