Yield to temptation. It may not pass your way again.

Then I glanced at the ring on my finger. The Snake That Eats Its Own Tail, Forever and Ever. I know where I came from—but where did all you zombies come from? I felt a headache coming on, but a headache powder is one thing I do not take. I did once—and you all went away. So I crawled into bed and whistled out the light. You aren’t really there at all. There isn’t anybody but me—Jane—here alone in the dark. I miss you dreadfully!

When the need arises - and it does - you must be able to shoot your own dog. Don't farm it out — that doesn't make it nicer, it makes it worse.

Nothing of value is free. Even the breath of life is purchased at birth only through gasping effort and pain... The best things in life are beyond money; their price is agony and sweat and devotion... and the price demanded for the most precious of all things in life is life itself--ultimate cost for perfect value

Never trust machinery more complicated than a knife and fork.

By the data to date, there is only one animal in the Galaxy dangerous to man -- man himself. So he must supply his own indispensable competition. He has no enemy to help him.

The nice thing about citing god as an authority is that you can prove anything you set out to prove.