The forest doesn't need us; we need the forest.

Where I am, I don't know, I'll never know, in the silence you don't know, you must go on, I can't go on, I'll go on.

Continuous learning is the only way to cope with rapid technological changes.

无论是正确的还是错误的，经济学家和政治哲学家的思想都比通常理解的有力。确实，世界不受其他任何事物统治。自信不被知识分子影响的那些所谓务实的人，往往只是几个过时经济学家思想的奴隶。（Concluding Notes. p. 383-384）

观察他交往的是什么人，就能知道他的品行如何。

验证不仅仅是发现错误；它关乎理解系统为何以某种方式工作。