最优财政政策要求税率随时间平稳变化，仅对政府支出的永久性变化作出反应。

我是个完美主义者，我承认这一点。我总是在努力改进。

The aim of every artist is to arrest motion, which is life, by artificial means and hold it fixed so that a hundred years later, when a stranger looks at it, it moves again since it is life.

Every fall is for a better stand up.

量子计算的美在于它能够利用量子力学的特性来获得计算优势。