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。

治理天下的人，就像牧马的人一样，关键是要除去害群之马。

【解释】人常常在忧患困苦中，才能磨练意志，增长才干。

No matter what , just do not give up .Always believe that your dream can come true & just keep working for what you want to achieve.

Thank God, under our Constitution there was no connection between church and state.

The best way to predict the future is to invent it.

Innovation in forestry means finding ways to do more with less.

逃脱历史重负的唯一方法就是书写它。