Meeting and sharing knowledge and crafts,

他们聚会并分享知识与工艺
Blending their similarities and differences.

融合了他们之间的相似与差异
In a word, they became civilized.

一句话他们变得文明了
But the only energy at their disposal was provided by nature...

但是他们唯一可以支配的能量来源于自然
And the strength of their bodies.

以及他们身体的力量
It was the story of humankind for thousands of years.

这是几千年来人类一成不变的经历
It still is for one person in four-

这仍旧是世界上四分之一的人类
Over one and a half billion human beings-

也就是超过15亿人类的经历
More than the combined population of all the wealthy nations.

这一数字超过了所有富裕国家的人口总和
Taking from the earth only the strictly necessary.

仅仅向地球索取必需品
For a long time, the relationship between humans and the planet...

很长一段时间里人类和地球的关系
Was evenly balanced.

是平衡的