More quotes by Carl Sagan

"A celibate clergy is an especially good idea, because it tends to suppress any hereditary propensity toward fanaticism."
"You can get into a habit of thought in which you enjoy making fun of all those other people who don't see things as clearly as you do. We have to guard carefully against it."
"Somewhere, something incredible is waiting to be known."
"The truth may be puzzling. It may take some work to grapple with. It may be counterintuitive. It may contradict deeply held prejudices. It may not be consonant with what we desperately want to be true. But our preferences do not determine what's true."
"Extraordinary claims require extraordinary evidence."