Theoretical physicists live in a classical world, looking out into a quantum-mechanical world. The latter we describe only subjectively, in terms of procedures and results in our classical domain.
"Introduction to the hidden-variable question" (1971), included in Speakable and Unspeakable in Quantum Mechanics (1987), p. 29
The concept of 'measurement' becomes so fuzzy on reflection that it is quite surprising to have it appearing in physical theory at the most fundamental level ... does not any analysis of measurement require concepts more fundamental than measurement? And should not the fundamental theory be about these more fundamental concepts?John Stewart Bell
I am a Quantum Engineer, but on Sundays I Have Principles.John Stewart Bell
Is it not good to know what follows from what, even if it is not necessarily FAPP? [FAPP is Bell's suggested abbreviation of "for all practical purposes."] Suppose for example that quantum mechanics were found to resist precise formulation. Suppose that when formulation beyond FAPP was attempted, we find an unmovable finger obstinately pointing outside the subject, to the mind of the observor, to the Hindu scriptures, to God, or even only Gravitation? Would that not be very, very interesting?John Stewart Bell