When a place gets crowded enough to require ID's, social collapse is not far away. It is time to go elsewhere. The best thing about space travel is that it made it possible to go elsewhere.

Never own more than you can carry in both hands at a dead run.

He should have known better because, early in his learnings under his brother Mahmoud, he had discovered that long human words (the longer the better) were easy, unmistakable, and rarely changed their meanings, but short words were slippery, unpredictable changing their meanings without any pattern. Or so he seemed to grok. Short human words were never like a short Martian word - such as grok which forever meant exactly the same thing. Short human words were like trying to lift water with a knife. And this had been a very short word.

The future is better than the past. Despite the crepe hangers, romanticists, and anti-intellectuals, the world steadily grows better because the human mind, applying itself to environment, makes it better. With hands ... with tools ... with horse sense and science and engineering.

Sin is cruelty and injustice, all else is peccadillo. Oh, a sense of sin comes from violating the customs of your tribe. But breaking custom is not sin even when it feels so; sin is wronging another person.

There is no safety this side of the grave

You have to give an editor something to change, or he gets fretful. After he pees in it, he likes the flavor better, so he buys it.