安全不是产品，而是一种能力。

Sometimes we get sad about things and we don’t like to tell other people that we are sad about them. We like to keep it a secret. Or sometimes, we are sad but we really don’t know why we are sad, so we say we aren’t sad but we really are.

Enjoyment appears at the boundary between boredom and anxiety, when the challenges are just balanced with the person’s capacity to act.

意识到社会结构的概念并敏感地使用它，就是能够在各种环境中追踪这种联系。