—— 请按键盘 空白键 开始游戏 ——

Mathematics knows no races or geographic boundaries; for mathematics, the cultural world is one country.
The truth is, the science of Nature has been already too long made only a work of the brain and the fancy: It is now high time that it should return to the plainness and soundness of observations on material and obvious things.
The world is full of magic things, patiently waiting for our senses to grow sharper.