I:  NATURE

Ultimate wisdom always consists in understanding the instinctive causes—that is:  a man must never fall into the madness of believing that he has really risen to be lord and master over Nature—which is so easily induced by the conceit of half-education—but must understand the fundamental necessity of Nature’s rule, and realize how much his existence is subject to these laws of eternal combat and upward struggle. Then he will sense that in a universe where planets revolve around suns, and moons turn about planets, where force alone forever masters weakness, compelling it to be an obedient servant or else crushing it, there can be no special laws for man. For him, too, the eternal principles of this ultimate wisdom hold sway. He can try to grasp them; but escape them, never.

I:10

When man tries to rebel against the iron logic of Nature, he comes into conflict with principles to which he himself owes his existence as man. And so his action against Nature must lead to his own downfall.

I:11

Here too, of course, Nature can be mocked for a certain time, but her revenge will not fail to appear.  It just takes time to manifest itself, or rather, it is often recognized too late by man.

I:10

Eternal Nature inexorably avenges the infringement of her commands. 

I:2

. . . This planet once moved through space for millions of years without human beings, and it can do so again some day if men forget that they owe their higher existence, not to the ideas of a few crazy ideologues, but to the knowledge and ruthless application of Nature’s iron-clad laws.

I:11

. . . It is life alone that all things must serve. 

I:8