Niels Bohr Quotes

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

Niels Bohr

#2. 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

#3. Nothing exists until it is measured.

Niels Bohr

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

Niels Bohr

#5. 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

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

#9. 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

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

Niels Bohr

#11. 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

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

Niels Bohr

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

Niels Bohr

#14. 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

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

Niels Bohr

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

Niels Bohr

#17. 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

#18. 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

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

#22. 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

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

#27. 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

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

Niels Bohr

#29. 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

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

Niels Bohr

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

Niels Bohr

#32. 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

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

Niels Bohr

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

Niels Bohr

#35. 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

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

Niels Bohr

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

Niels Bohr

#38. 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

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

Niels Bohr

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

Niels Bohr

#41. 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

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

Niels Bohr

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

Niels Bohr

#44. 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

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

Niels Bohr

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

Niels Bohr

#47. 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

#48. Truth and clarity are complementary

Niels Bohr

#49. We are suspended in language.

Niels Bohr

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

Niels Bohr

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

Niels Bohr

#52. 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

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

Niels Bohr

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

Niels Bohr

#55. 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

#56. 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

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

#67. 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

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

Niels Bohr

#69. 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

#70. 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

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

#74. 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

#75. 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

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

Niels Bohr

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

Niels Bohr

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

Niels Bohr

#79. Never express yourself more clearly than you are able to think

Niels Bohr

#80. Anyone who can contemplate quantum mechanics without getting dizzy hasn't understood it.

Niels Bohr

#81. Prediction is very difficult, especially about the future.

Niels Bohr

#82. If we couldn't laugh at ourselves, that would be the end of everything.

Niels Bohr

#83. Prediction is difficult, especially the future.

Niels Bohr

#84. Of course I don't believe in it [pointing to horseshoe on his office wall]. But I understand that it brings you luck whether you believe in it or not.

Niels Bohr

#85. Sometimes the child in one behaves a certain way and the rest of oneself follows behind, slowly shaking its head.

Niels Bohr

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

Niels Bohr

#87. [About describing atomic models in the language of classical physics:]
We must be clear that 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 and establishing mental connections.

Niels Bohr