The gods do not protect fools. Fools are protected by more capable fools. She'd - Larry Niven

Drugs: “There’s no way to keep them from getting in. Anyone who wants drugs can get them. We make arrests where we can, and so what? Me, I’m betting on Darwin.”
“How do you mean?”
“The next generation won’t use drugs because they’ll be descended from people who had better sense.”

Sometimes you just have to be satisfied with what you are.

Anyone who says human nature can’t be changed is out of his head. To make it stick, he’s got to define human nature—and he can’t.