Bohr, Niels

"Those who are not shocked when they first come across quantum mechanics cannot possibly have understood it."

"The task is not to understand nature, but to learn to ask nature the right questions."

"When I hear of Schrödinger's cat, I reach for my gun."

"Life is not a problem to be solved but a reality to be experienced."

"We are all agreed that your theory is crazy. The question that divides us is whether it is crazy enough."

"For a parallel between the limits of knowledge and our freedom of will, one should perhaps compare the uncertainty principle not with determinism but with the old problem of free will."

"The great challenge is to remain faithful to the principles of inquiry while acknowledging the strange nature of atomic reality."

"Modern physics has taught us that the nature of any object can only be described in relation to the object's interaction with something else."

"The atoms or elementary particles themselves are not real; they form a world of potentialities."

"I would say that the task is not to imagine how nature is and that it is, but rather to imagine how it might appear to us."

"Understanding means coming to terms with the primary fact of one's existence."

"The purpose of life is not to find meaning. It is to create meaning."

"Difficulty and opposition are only opportunities in disguise."

"The depth of friendship does not depend on length of acquaintance."

"One should as a rule respect public opinion in so far as is necessary to avoid starvation and to prevent oneself from being cast into prison, but anything that goes beyond this is voluntary submission to an unnecessary tyranny."

"Patience is the companion of wisdom."

"The story of human progress is not one of continuous upward ascent."

"Language is not only a tool for expression but also a constraint on what can be thought."

"The development of science presupposes a constant revision of what we believe to be true."

"No important induction comes from the mere observation of nature alone."

"The scientist only imposes his theories on nature to the extent that his observations are guided by those theories."

"The fundamental postulates of a science are as arbitrary as the axioms of Euclidean geometry."

"The existence of life on earth is a consequence of quantum mechanics."

"The problems that exist in the world cannot be solved by the level of thinking that created them."

"Human language is inherently incapable of capturing the truth of the physical world."

"In physics, you don't have to go around making trouble for yourself – nature does it for you."

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

"The new ideas and experiences of this epoch press forward."

"The most important discoveries will provide answers to questions that we have not yet learned to ask."

"A great truth is a truth whose negation is also a great truth."