绵绵若存，用之不勤
天地万物，是取之不尽，用之不竭的吗？几千年前老子就指出，宇宙延绵不绝，却不能滥用，否则就是在消耗生命的元神了。 人类社会发展史，是伤及天地的历史，相比之下，更是一部倒退的进化史。
古人意识到，生养万物的谷神是永恒长存的，【谷】是空虚幽深的山谷，【神】是形容【道】的神奇，它如同母亲的子宫，是孕育生命的出口，是天地的根本。宇宙的生命若有若无，万世长存，不能过度使用。
道德经第六章 原文
谷神不死，是谓玄牝[pìn]。玄牝之门，是谓天地根。绵绵若存，用之不勤。
The Spirit of the Valley never dies,
It is called the Mystic Female,
The Door of the Mystic Female,
Is the root of Heaven and Earth.
Continuously, continuously,
It seems to remain.
Draw upon it,
And it serves you with ease.
-- Lin Yutang 林语堂
The Valley Spirit never dies,
It is named the Mysterious Female,
And the doorway of the Mysterious Female,
Is the base from which Heaven and Earth sprang,
It is there within us all the while,
Draw upon it as you will, it never runs dry.
-- Arthur Waley 亚瑟·威利
