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！"
大多数人的问题在于他们用希望、恐惧或愿望思考，而不是用头脑。
"The colony is the place where the project of a new humanity is to be tested, where the dream of a world without borders is to be realized, where the dream of a world without races is to be realized, where the dream of a world without nations is to be realized, where the dream of a world without classes is to be realized, where the dream of a world without genders is to be realized."
In computer science, we stand on the shoulders of giants.
可持续性不仅仅是一个目标，更是我们对后代的责任。