Bohr's Quotes

#1. Copenhagen interpretation Niels Bohr's combination of instrumentalism, anthropocentrism and studied ambiguity, used to avoid understanding quantum theory as being about reality.

David Deutsch

#2. The non-commutativity of the underlying process produces an ontological complementarity. This must be contrasted to Bohr's epistemological complementarity.

Basil Hiley

#3. Physics is the belief that a simple and consistent description of nature is possible.

Niels Bohr

#4. There are some things so serious you have to laugh at them.

Niels Bohr

#5. There is no hope for any speculation that does not look absurd at first glance.

Niels Bohr

#6. I go into the Upanishads to ask questions.

Niels Bohr

#7. The measurement we get when we measure something is not a property of the thing measured.

Niels Bohr

#8. There are some things so serious that you have to laugh at them.

Niels Bohr

#9. I admired Bohr very much. We had long talks together, long talks in which Bohr did practically all the talking.

Paul Dirac

#10. It is wrong to think that the task of physics is to find out how Nature is. Physics concerns what we say about Nature.

Niels Bohr

#11. Sommerfeld's fine-structure theory was generally considered to be excellently and unambiguously confirmed by experiment. Because the theory rested on the foundation provided by Bohr, the experiments were also taken as strong support for his theory of atomic structure.

Helge Kragh

#12. In our description of nature the purpose is not to disclose the real essence of the phenomena but only to track down, as far as possible, relations between the manifold aspects of our experience.

Niels Bohr

#13. Anybody who is not shocked by this subject has failed to understand it. [of quantum mechanics]

Niels Bohr

#14. It is not enough to be wrong, one must also be polite.

Niels Bohr

#15. All rising curves that show unwelcome trends in human affairs will approach infinity if extended far enough, but it is we who dictate the curve and not vice versa.

Niels Bohr

#16. An expert is a person who has made all the mistakes that can be made in a very narrow field.

Niels Bohr

#17. Margrethe: And when all our eyes are closed, when even the ghosts have gone, what will be left of our beloved world? Our ruined and dishonoured and beloved world?

Michael Frayn

#18. Bohr: Heisenberg, I have to say - if people are to be measured strictly in terms of observable quantities ...
Heisenberg: Then we should need a strange new quantum ethics.

Michael Frayn

#19. Accuracy and clarity of statement are mutually exclusive.

Niels Bohr

#20. We are suspended in language.

Niels Bohr

#21. Truth and clarity are complementary

Niels Bohr

#22. We are all agreed that your theory is crazy. The question which divides us is whether it is crazy enough to have a chance of being correct. My own feeling is that it is not crazy enough.

Niels Bohr

#23. We are trapped by language to such a degree that every attempt to formulate insight is a play on words.

Niels Bohr

#24. We all know your idea is crazy. The question is whether it is crazy enough.

Niels Bohr

#25. Fermi turned to Bohr with weary eyes and a slanted smile, and shrugged. "So we thought we had discovered new elements. We even named them - hesperium, ausonium. Wrong! Mythical! They were ordinary old barium and iodine. We were careful - too careful.

Gregory Benford

#26. A physicist visits a colleague and notices a horseshoe hanging on the wall above the entrance. 'Do you really believe that a horseshoe brings luck?' he asks. 'No,' replies the colleague, 'but I've been told that it works even if you don't believe in it.'

Niels Bohr

#27. Your theory is crazy, but it's not crazy enough to be true.

Niels Bohr

#28. Nobody knows how the stand of our knowledge about the atom would be without him. Personally, Bohr is one of the amiable colleagues I have met. He utters his opinions like one perpetually groping and never like one who believes himself to be in possession of the truth.

Albert Einstein

#29. Everything we call real is made of things that cannot be regarded as real.

Niels Bohr

#30. One must always do what one really cannot.

Niels Bohr

#31. Since Einstein developed his theory of relativity, and Rutherford and Bohr revolutionised physics, our picture of the world has radically changed.

A. N. Wilson

#32. There's a quote from the famous physicist Niels Bohr, who posits that the way you become an expert in a field is to make every mistake possible in that field.

Sebastian Gutierrez

#33. If you aren't confused by quantum mechanics, you haven't really understood it.

Niels Bohr

#34. Rutherford is a man you can rely on; he comes regularly and enquires how things are going and talks about the smallest details - Rutherford is such an outstanding man and really interested in the work of all the people around him.

Niels Bohr

#35. The present state of atomic theory is characterized by the fact that we not only believe the existence of atoms to be proved beyond a doubt, but also we even believe that we have an intimate knowledge of the constituents of the individual atoms.

Niels Bohr

#36. If you think you understand it, that only shows that you don't know the first thing about it.

Niels Bohr

#37. Anyone who is not shocked by quantum theory has not understood it.

Niels Bohr

#38. When Einstein later complained that "God does not play dice with the world," Bohr reportedly fired back, "Stop telling God what to do.

Michio Kaku

#39. Perhaps I have found out a little about the structure of atoms.

Niels Bohr

#40. Chemistry, until my childhood, not that long ago, was regarded as a calculating device. Because you couldn't reduce to physics. So it's just some way of calculating the result of experiments. The Bohr atom was treated that way.

Noam Chomsky

#41. When [Niels] Bohr is about everything is somehow different. Even the dullest gets a fit of brilliancy.

Isidor Isaac Rabi

#42. If you have a correct statement, then the opposite of a correct statement is of course an incorrect statement, a wrong statement. But when you have a deep truth, then the opposite of a deep truth may again be a deep truth.

Niels Bohr

#43. If one reads the biographies of physicists like Bohr, Heisenberg, Chandrashekhar, and Bethe, one gets the impression that without hikes in the mountains and the vision of night skies their science would not have amounted to much.

Mihaly Csikszentmihalyi

#44. The great extension of our experience in recent years has brought light to the insufficiency of our simple mechanical conceptions and, as a consequence, has shaken the foundation on which the customary interpretation of observation was based.

Niels Bohr

#45. A deep truth is a truth so deep that not only is it true but it's exact opposite is also true.

Niels Bohr

#46. Every valuable human being must be a radical and a rebel, for what he must aim at is to make things better than they are

Niels Bohr

#47. Isolated material particles are abstractions, their properties being definable and observable only through their interaction with other systems .

Niels Bohr

#48. The best weapon of a dictatorship is secrecy, but the best weapon of a democracy should be the weapon of openness.

Niels Bohr

#49. Anyone not shocked by quantum mechanics has not yet understood it.

Niels Bohr

#50. The opposite of every great idea is another great idea.

Niels Bohr

#51. The meaning of life consists in the fact that it makes no sense to say that life has no meaning.

Niels Bohr

#52. You must come to Copenhagen to work with us. We like people who can actually perform thought experiments!

Niels Bohr

#53. Some subjects are so serious that one can only joke about them.

Niels Bohr

#54. What is that we human beings ultimately depend on? We depend on our words. We are suspended in language. Our task is to communicate experience and ideas to others.

Niels Bohr

#55. Truth is something that we can attempt to doubt, and then perhaps, after much exertion, discover that part of the doubt is not justified.

Niels Bohr

#56. Today, all physicists know from studying Einstein and Bohr that sometimes an idea which looks completely paradoxical at first, if analyzed to completion in all detail and in experimental situations, may, in fact, not be paradoxical.

Richard P. Feynman

#57. Oh what idiots we have all been, this is just as it must be

Niels Bohr

#58. Predition is risky, especially of the future.

Niels Bohr

#59. The old saying of the two kinds of truth. To the one kind belongs statements so simple and clear that the opposite assertion obviously could not be defended. The other kind, the so-called 'deep truths', are statements in which the opposite also contains deep truth.

Niels Bohr

#60. Predictions are hard, especially abot the future.

Niels Bohr

#61. No, no, you're not thinking; you're just being logical.

Niels Bohr

#62. When it comes to atoms, language can be used only as in poetry. The poet, too, is not nearly so concerned with describing facts as with creating images.

Niels Bohr

#63. Those who are not shocked when they first come across quantum theory cannot possibly have understood it.

Niels Bohr

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

Niels Bohr

#65. And anyone who thinks they can talk about quantum theory without feeling dizzy hasn't yet understood the first thing about it.

Niels Bohr

#66. A person who wasn't outraged on first hearing about quantum theory didn't understand what had been said.

Niels Bohr

#67. In a sense the debate between Penrose and Hawking is a continuation of that earlier argument, with Penrose playing the role of Einstein and Hawking that of Bohr.

Stephen Hawking

#68. Some things are so serious, they can only be joked about.

Niels Bohr

#69. Many studies of research scientists have shown that achievement (at least below the genius level of an Einstein, Bohr, or a Planck) depends less on ability in doing research than on the courage to go after opportunity.

Peter Drucker

#70. Every great and deep difficulty bears in itself it's own solution. It forces us to change our thinking in order to find it.

Niels Bohr

#71. In the great drama of existence we are audience and actors at the same time.

Niels Bohr

#72. In March 1950, in New York City, I was married to Marietta Soffer. We have three children: Vilhelm, Tomas, and Margrethe.

Aage Bohr

#73. Nothing exists until it is measured.

Niels Bohr

#74. If anybody says he can think about quantum physics without getting giddy, that only shows he has not understood the first thing about them.

Niels Bohr

#75. The opposite of a plain truth, Neils Bohr liked to repeat, is a plain falsehood. But the opposite of a deep truth is another deep truth.

Rebecca Goldstein

#76. Address to Albert Einstein: You are not thinking. You are merely being logical.

Niels Bohr

#77. The legendary Danish physicist Niels Bohr distinguished two kinds of truths. An ordinary truth is a statement whose opposite is a falsehood. A profound truth is a statement whose opposite is also a profound truth.

Frank Wilczek

#78. It is, indeed, perhaps the greatest prospect of humanistic studies to contribute through an increasing knowledge of the history of cultural development to that gradual removal of prejudices which is the common aim of all science.

Niels Bohr

#79. Prediction," as Niels Bohr liked to say, "is very difficult, especially if it's about the future.

Steven D. Levitt

#80. A physicist is just an atom's way of looking at itself.

Niels Bohr

#81. It is difficult to predict, especially the future.

Niels Bohr

#82. One thought spectra are marvellous, but it is not possible to make progress there. Just as if you have the wing of a butterfly then certainly it is very regular with the colors and so on, but nobody thought one could get the basis of biology from the coloring of the wing of a butterfly.

Niels Bohr

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

Niels Bohr

#84. It is the hallmark of any deep truth that its negation is also a deep truth

Niels Bohr

#85. When searching for harmony in life one must never forget that in the drama of existence we are ourselves both actors and spectators.

Niels Bohr

#86. It is very difficult to make an accurate prediction, especially about the future.

Niels Bohr

#87. Physics is not about how the world is, it is about what we can say about the world

Niels Bohr

#88. There are trivial truths and there are great truths. The opposite of a trivial truth is plainly false. The opposite of a great truth is also true.

Niels Bohr

#89. The opposite of a fact is falsehood, but the opposite of one profound truth may very well be another profound truth.

Niels Bohr

#90. An expert is a man who has made all the mistakes which can be made in a very narrow field.

Niels Bohr

#91. You are not thinking, you are just being logical.

Niels Bohr

#92. When we measure something we are forcing an undetermined, undefined world to assume an experimental value. We are not measuring the world, we are creating it.

Niels Bohr

#93. If quantum mechanics hasn't profoundly shocked you, you haven't understood it yet.

Niels Bohr

#94. Our task is not to penetrate the essence of things, the meaning of which we do not know anyway, but rather to develop concepts which allow us to talk in a productive way about phenomena in nature

Niels Bohr

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

Niels Bohr

#96. Stop telling God what to do with his dice.

Niels Bohr

#97. You can recognize a small truth because its opposite is a falsehood. The opposite of a great truth is another truth.

Niels Bohr

#98. An independant reality in the ordinary physical sense can neither be ascribed to the phenomenon nor to the agencies of observation.

Niels Bohr

#99. There are two sorts of truth: trivialities, where opposites are clearly absurd, and profound truths, recognised by the fact that the opposite is also a profound truth

Niels Bohr

#100. It is a great pity that human beings cannot find all of their satisfaction in scientific contemplativeness.

Niels Bohr