Niels Bohr

"In seeking the truth we must ask ourselves questions we have never asked before."

"The universe reveals its deepest secrets only to those patient enough to listen."

"We must not forget that the scientific method is not the only way to understand the world."

"The spectator is as important in physics as the observed phenomenon."

"Life's tragedy is that we get old too soon and wise too late."

"When you find a fault, do not speak it out loud, do the necessary work to mend it."

"The laws of physics are the canvas upon which the artist paints the picture of the universe."

"A physicist is someone who believes he has understood a problem after working on it for only a year."

"We must not retreat into the comfortable world of illusion just because reality is difficult to understand."

"The moment we stop questioning is the moment we stop being scientists."

"An idea that does not at first seem insane has no hope of being profoundly original."

"The uniqueness of each moment is what gives life its meaning and beauty."

"We cannot know, as a matter of principle, the present in all its details."

"The best way to predict the future is to understand the past."

"Nature respects no boundaries—neither geographical nor intellectual."

"Success in science depends upon the ability to imagine possibilities that do not yet exist."

"The greatest scientific discoveries often come from asking the simplest questions."

"In the atomic realm, uncertainty is not a limitation of our knowledge but a fundamental feature of reality."

"We are made of stardust, and the atoms in our bodies were forged in the hearts of dying stars."

"The human mind is not designed to understand the quantum world without significant effort and imagination."

"If you have not yet discovered paradoxes in nature, you have not yet begun to think deeply."

"An expert is a person who has made all the mistakes that can be made in his field."

"The task is not so much to see what no one has yet seen, but to think what nobody has yet thought about that which everybody sees."

"Prediction is very difficult, especially if it's about the future."

"How wonderful that we have met with a paradox. Now we have some hope of making progress."

"Truth and clarity are complementary."

"I go away, but the questions remain."

"Contraries are not contradictories."

"The opposite of a correct statement is a false statement. But the opposite of a profound truth may well be another profound truth."

"Every sentence I utter must be understood not as an affirmation, but as a question."