The most significant threat to liberal democracy today is not from rival ideologies like communism or fascism, but from within—from the rise of populism and the erosion of democratic norms.

解析：知行工夫本不可离。

Happiness is like a butterfly; the more you chase it, the more it will elude you. But if you turn your attention to other things, it will come and sit softly on your shoulder.

The only thing we have to fear is fear itself.

年轻人不知道什么是谨慎，因此他们尝试不可能的事情——并且一代又一代地实现了它。

一个值得追求的年度目标：充分学习一个领域，以至于你无法相信一年前有多么无知。