有人居住的世界的边界是由人类知识的极限决定的。

解释：大树不能生长在屋脊上，松柏不能生长在矮墙上。

Short-term gains at the expense of the environment will always lead to long-term losses.

I've learned that you shouldn't go through life with a catcher's mitt on both hands; you need to be able to throw something back.