Farmers are the first environmentalists, working with nature every day.

All the effects of nature are only the mathematical consequences of a small number of immutable laws.

Good econometrics is like good carpentry—it's all about using the right tool for the job.

The world is a fine place and worth fighting for.

成功不是幸福的关键。幸福才是成功的关键。如果你热爱你所做的事情，你就会成功。