A brief caveat re. Paul's invocation of Einstein vs. Bohr.
Bohr's position on quantum mechanics did not stem from a
general anti-realist philosophical orientation; rather it
was based on the specific scientific problems that arise in
attempting a realist interpretation of quantum mechanics in
particular. Unless you postulate a system of hidden
variables of a particularly complex sort -- which tends to
fall foul of Occam, since this apparatus gives no predictive
advantage whatever -- realism in re. quantum mechanics gives
predictions incompatible with the experimental results.
Allin Cottrell