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 BohrThe 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 BohrThe opposite of a fact is falsehood, but the opposite of one profound truth may very well be another profound truth.
Niels BohrEvery great and deep difficulty bears in itself its own solution. It forces us to change our thinking in order to find it.
Niels Bohr