小毛头！你不知道我们是敌人吗？

What a pinhead! Don't you know we're enemies?

youdao

我们以前是最好的朋友，现在我们是敌人。

We used to be best friends; now, we are enemies.

youdao

当然与运营商的合作也很重要，他们以前一向当我们是敌人。

And the partnerships with carriers — they had thought of us as an enemy.

youdao

At least we figured out who the enemy was.

至少我们弄清了敌人是谁。

普林斯顿公开课 - 国际座谈会课程节选

So how can we say that " justice means helping friends and harming enemies," : Socrates asks, "when we may not even be sure " who our friends and our enemies really are?

所以我们如何能说,正义意指协助朋友并打击敌人“,苏格拉底提问，“尤其是当我们甚至无法确定,谁是真正的朋友及敌人？

耶鲁公开课 - 政治哲学导论课程节选

To say giving bad news to an enemy is reinforcing because it makes the enemy feel bad doesn't say anything different from giving bad news to an enemy feels good because we like to give bad news to an enemy.

由于使敌人感到不快,而认定向敌人散布坏消息是强化行为,这与因为我们想要敌人听到坏消息,而向心情良好的敌人散布坏消息,没什么区别。

耶鲁公开课 - 心理学导论课程节选