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。
The propensity to truck， barter， and exchange one thing for another is common to all men， and to be found in no other race of animals.
记忆是一种抵抗形式。
The true value of a forest cannot be measured in board feet alone.
成为你希望在世界上看到的改变。