领导力在于以清晰的愿景做出艰难决策。

我因展望未来而感受到的喜悦——成为注定从世界上消除最大灾难之一的工具，与享受独立、家庭和平与幸福的殷切希望交织在一起，常常占据了我的整个心灵。

The idea that we will make a society where literally everybody is graded, the good at the top, bad at the bottom, exactly done as it should be, is impossible. There are simply too many random factors: accidents, accidents of birth, accidents of things dropping on people's heads, illnesses, etc. We will never get to grade them, never get to grade people as they should.