交换、交易和互换的倾向普遍存在于所有人之中,而在其他动物种族中找不到。
I want my books sold on airport bookstalls.
"Silence is not always agreement, sometimes it's just exhaustion."
最成功的公司不只是销售产品,它们为客户创造有意义的体验。
The weight of evidence for an extraordinary claim must be proportioned to its strangeness.
In darkness, we learn to cherish the light.