Robert A. Heinlein vs. Friedrich Nietzsche

"Jealousy is a disease, love is a healthy condition. The immature mind often mistakes one for the other, or assumes that the greater the love, the greater the…"

"Love is that condition in which the happiness of another person is essential to your own."

"May you live as long as you wish and love as long as you live."

"“People tend to fall into three psychological types, all differently motivated. There is the type, motivated by economic factors, money...And there is the ty…"

"He gave up and went back to loafing, found that he could sleep all right in the afternoons but that the practice kept him awake at night."

"I really am a good listener because you never can tell when you will pick up something useful—and all in the world any woman has to do to be considered “char…"

"Mr. Stone was satisfied, being sure in his heart that any person skilled with mathematical tools could learn anything else he needed to know, with or without…"

"Luck is a bonus that follows careful planning—it’s never free."

"As for population, every major shortcoming of our native planet could be traced to one cause: too many people, not enough planet."

"When you haven’t data, guessing is illogical."

"Since when did a mathematician need any tools but his own head? Pythagoras had done well enough with a stick and a stretch of sand."

"I have never been impressed by the formal schools of ethics. I had sampled them — public libraries are a ready source of recreation for an actor short of cas…"

"Don, have you been dealing with a booklegger?"

"You can have peace. Or you can have freedom. Don't ever count on having both at once."

"Three things only do slaves require, food, work, and their gods, and of the three their gods must never be touched, else they grow troublesome."

"Apparently she believes she is safe. Evil is essentially stupid, Joe; despite her brilliance, she believes what she wishes to believe. Or it may be that she …"

"Sex is rearing its interesting head."

"Widows are far better than brides. They don't tell, they won't yell, they don't swell, they rarely smell, and they're grateful as hell."

"Time after time he had fallen into the Cartesian fallacy, mistaking clear reasoning for correct reasoning."

"I now define "moral behavior" as "behavior that tends toward survival." I won't argue with philosophers or theologians who choose to use the word "moral" to …"