The ecosystem of our world is a closed system: it would run out of gas, collapse of its own weight.

The ecosystem of our world is a closed system: it would run out of gas, collapse of its own weight.

我们这个世界的生态系统是一个封闭的系统:它会耗尽所有的气体，自行崩溃。

-- Joan D. Vinge 琼·D·温格