Certainty of evidence does not lead to certainty of belief.

The most important political development of the last half century has been the spread of liberal democracy around the world.

Success is not about being the best, it's about being the most adaptable.

释义：过于强硬的弓弦容易断裂，过于锋利的刀口容易受损。惹祸往往是因为多嘴多舌，招致灾祸多是因为心肠狠毒。