我唯一能依靠的就是我自己的不确定性。

教学应服从于人类心智发展的规律。

译文：人的福分，并不是靠外在的条件和环境得来的，而是取决于自己内心的修养和行为。只有把握好自己的内心，才能获得真正的幸福和成功。

The magi, as you know, were wise men—wonderfully wise men—who brought gifts to the Babe in the manger. They invented the art of giving Christmas presents. Being wise, their gifts were no doubt wise ones, possibly bearing the privilege of exchange in case of duplication.

我们数量增长到如此地步，以至于我们的存在像疾病一样明显削弱了地球。

最好的艺术是诚实的艺术。