It seems to me that if you or I must choose between two courses of thought or action, we should remember our dying and try so to live that our death brings no pleasure to the world.

The mother-child relationship is paradoxical and, in a sense, tragic. It requires the most intense love on the mother's side, yet this very love must help the child grow away from the mother, and to become fully independent.

心智是一套信息处理机器，它们由自然选择设计来解决我们狩猎采集祖先面临的适应性问题。