To live is to choose, and to choose is to renounce.

谁统治东欧，谁就掌控了心脏地带；谁统治心脏地带，谁就掌控了世界岛；谁统治世界岛，谁就掌控了世界。

Never stop questioning how things can be done better—complacency is the enemy of progress.

Everything is hard before it is easy. The day before something is a breakthrough， it’s a stupid idea.

The man who is anybody and who does anything is surely going to be criticized, vilified, and misunderstood.

自动机和形式语言的研究对于理解计算的极限是基础性的。