我们不能一直用老方法做事。世界已经改变，我们也必须改变。
We can’t just keep doing things the way we’ve always done them. The world has changed, and so must we.
I don't sing because I'm happy; I'm happy because I sing.
学习在于改变介于刺激和反应之间的某些中介过程。
The whole of life is just like watching a film. Only it's as though you always get in ten minutes after the big picture has started, and no-one will tell you the plot, so you have to work it out all yourself from the clues.
I’ve learned that life is too short to be anything but happy.
The preservation of the means of knowledge among the lowest ranks is of more importance to the public than all the property of all the rich men in the country.