Classical physics

• In his letters with Pauli (1955), Bohr says that the situation in quantum mechanics is not essentially different from the situation in classical physics. He says that it was a mistake to think that classical physics permits a god’s eye description (where the situation of the describer makes no difference for the description).

  “I mean that you are yourself as inconsequent [inconsistent] in stressing the difference in such respect between classical and quantum mechanics. It is true that, before the epistemological aspects of the observational problem were so widely cleared up, a certain confusion was prevalent, but after the thorough lesson which we have received, the whole situation including that of classical mechanics appears in a new light.”

  Bohr’s statement here meshes with what he says elsewhere about the complementarity of energy and temperature in thermodynamics.