To travel is to write with your feet.
If a Nation expects to be ignorant and free in a state of civilization,it expects what never was and never will be....If we are to guard against ignorance and remain free,it is the responsibility of every American to be informed."
过去是一个异国;他们在那里的做法不同。
矩阵力学是对经典物理学的彻底背离,但它是解释原子世界所必需的。