“When you realize there is something you don't understand, then you're generally on the right path to understanding all kinds of things.”

“Although you may not stumble across a Martian in the garden, you might stumble across yourself. The day that happens, you'll probably also scream a little. And that'll be perfectly all right, because it's not every day you realize you're a living planet dweller on a little island in the universe.”

“You can never know if a person forgives you when you wrong them. Therefore it is existentially important to you. It is a question you are intensely concerned with. Neither can you know whether a person loves you. It’s something you just have to believe or hope. But these things are more important to you than the fact that the sum of the angles in a triangle is 180 degrees. You don't think about the law of cause and effect or about modes of perception when you are in the middle of your first kiss.”

“But understanding will always require some effort. You probably wouldn't admire a friend who was good at everything if it cost her no effort.”

“Then you have a big problem, because a human is a thinking animal. If you don't think, you're not really a human.”

“Dear Hilde, if the human brain was simple enough for us to understand, we would still be so stupid that we couldn't understand it. Love, Dad.”

“Life is short for those who are truly able to understand that one day the entire world will come to a complete end. Not everyone is capable of that. Not everyone has the ability to comprehend what going away for all eternity really implies. There are too many distractions, hour by hour, minute by minute, to hinder such an understanding.”