Kindness can be a revolutionary act in a world that often rewards selfishness.

Our heroes are human heroes. That's a very new situation. Most other societies have had, right at their center, the worship of something transcendent: a god, a spirit, a natural force, the universe, whatever it is -- something else that is being worshiped. We've slightly lost the habit of doing that, which is, I think, why we're particularly drawn to nature.

了解心灵的方法是对其进行逆向工程：弄清楚自然选择设计它来完成什么任务。