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！"

In the vastness of the cosmos, we are but a speck, yet our curiosity knows no bounds.

我们需要成为解决方案的一部分，而不是问题的一部分。

The brain caps off its second and last growth spurt in your 20s as it rewires itself for adulthood.

The creation of a modern state is a complex and difficult process that requires the development of strong institutions.

人は、失敗から学ぶことで成長する。