"Sometimes the hardest thing in life is to know which bridge to cross and which to burn."

The man who is fit to work at any particular trade is unable to understand the science of that trade without the kindly help and cooperation of men of a totally different type of education.

A mind needs books like as word needs a whetstone.

Documentation is like term insurance: It satisfies because almost no one who subscribes to it depends on its benefits.

世界充满了神奇的事物，耐心地等待我们的感官变得更加敏锐。