All of this we can associate with the pleasure principle.

这些我们都可以和快乐原则联系起来。

耶鲁公开课 - 文学理论导论课程节选

Add up all the pleasures, subtract all the pains.

把所有快乐加起来减去所有痛苦。

耶鲁公开课 - 死亡课程节选

Let's go to the excitement,to the fun.

让我们兴奋起来，快乐起来。

哈佛公开课 - 幸福课课程节选

You can't just add up all the pleasures and subtract the pains, or add up all the accomplishments and subtract the failures, or add up all the knowledge and subtract the ignorance and deception.

你不能只是把快乐加起来然后减去痛苦，或者仅是把成功相加再减去失败，或者把学问相加再减去蒙昧和欺骗。

耶鲁公开课 - 死亡课程节选