“[When a religious couple wrote to Sagan about fulfilled prophecies, he wrote back in May 1996:]If ‘fulfilled prophecy’ is your criterion, why do you not believe in materialistic science, which has an unparalleled record of fulfilled prophecy? Consider, for example, eclipses.”

“Prophecy is history unfulfilled, and history is prophecy fulfilled.”

“Believe in yourself. Under-confidence leads to a self-fulfilling prophecy that you are not good enough for your work.”

“Self-doubt is a self-fulfilling prophecy.”

“Likewise, if we offer too much silent assent about mysticism and superstition - even when it seems to be doing a little good - we abet a general climate in which scepticism is considered impolite, science tiresome, and rigorous thinking somehow stuffy and inappropriate.”

“One of the reasons for its success is that science has a built-in, error-correcting machinery at its very heart. Some may consider this an overbroad characterization, but to me every time we exercise self-criticism, every time we test our ideas against the outside world, we are doing science. When we are self-indulgent and uncritical, when we confuse hopes and facts, we slide into pseudoscience and superstition.”

“If we offer too much silent assent about mysticism and superstition - even when it seems to be doing a little good - we abet a general climate in which scepticism is considered impolite, science tiresome, and rigorous thinking somehow stuffy and inappropriate. Figuring out a prudent balance takes wisdom.”