Niels Bohr

"When you come to a fork in the road, take it."

"Genius is like a lightning bolt—it strikes when it will and where it will."

"The same quantum mechanical principles that govern atoms also govern galaxies."

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

"We must be clear that when it comes to atoms, language can be used only as in poetry."

"The great difference between science and philosophy is that science asks questions it can answer, while philosophy asks questions it cannot."

"Electrons are not things, they are possibilities."

"The very fact that the totality of our sense experiences is such that by means of thinking we can lay down laws for it proves that reality is independent of us."

"I would rather be clear and wrong than obscure and right."

"The world is not only stranger than we imagine, it is stranger than we can imagine."

"Sometimes I despair that we have not found a way to help people understand the quantum world."

"A great discovery is not made by accident but by hard work combined with a keen eye and an alert mind."

"The quantum world is a world of probabilities, not certainties."

"The purpose of physics is to provide a description of nature in the simplest possible terms."

"Every great scientific truth goes through three stages: first, people deny it; second, they say it violates the Bible; third, they say they believed it all along."

"Our task is to understand the invisible laws that govern visible phenomena."

"The seed of great discovery is often found in great confusion."

"When faced with a great truth, one's first reaction is not belief but bewilderment."

"The more you know, the more you realize how much you do not know."

"It is the duty of a scientist not just to pursue knowledge but to communicate it."

"Human knowledge is founded on the assumption that our minds can receive impressions of the outside world."

"We should be humble about our knowledge but bold in our questioning."

"Those who attempt to found a system of philosophy without having mastered mathematics are lost."

"The richness of nature expresses itself in an infinite number of ways which we are far from exhausting."

"Truth and clarity must always accompany each other."

"The great strength of science is its ability to admit error and move forward."

"Most of the fundamental ideas of science are essentially simple, and may, as a rule, be expressed in a language comprehensible to everyone."

"I never think of the future—it comes soon enough."

"The atomic nucleus is a miniature solar system, but the laws that govern it are fundamentally different."

"A real difficulty exists only when the mind is not sufficiently prepared to face it."